Minor dietary components may play an important role in atherogenesis as major components like lipids and carbohydrates. Correlation analysis between the standarized mortality of coronary heart disease (CHD) and nutrient components by Knox revealed that animal protein, calcium and ascorbic acid (vitamin C) had protective effects to CHD as shown in Table 1. Gey reported that high incidence of low plasma level of ascorbic acid and tocopherol in the people of the countries with high incidence of coronary heart death. These epidemiological studies ascertained contribution of minor dietary components to atherogenesis. As one of minor dietary components, role of ascorbic acid in atherogenesis are discussed in this presentation.
As previously reported, ascorbic acid deficiency induced the endothelial injury in guinea pig and marginal deficiency for prolonged period induced atherosclerotic lesions as shown in Fig. 1 without supplement of cholesterol in the diet. Collagen in the arota, in particular, type I collagen as reported by Ginter was depleted of their content by the deficiency. On the contrary, an increase in aortic acid mucopolysaccharide which supposed to be secondary response to atherogenic process, was observed.
To estimate smooth muscle function in scurvy, developed tension of the aorta to vasoactivators such as norepinephrine, prostaglandin F_2α, 5-hydroxytryptophan and histamine were determined with helical strips of the aorta. The aorta of scurvy showed decreased tension to the vasoactivators as shown in Fig. 3. The results suspect altered or reduced receptors to the agents due to cell membrane alteration by ascorbic acid deficiency. These findings revealed specific effects of ascorbic acid to maintaine integrity of the endothelium, extracellular matrix and smooth muscle cell function ofthe arterial wall.
Influences of ascorbic acid on lipoprotein metabolism are also studied. In scurvy, increase in serum VLDL and LDL were observed as shown in Fig. 4. Following mechanisms of hyperlipidemia are postulated. That is, depressed lipoprotein lipase activity following endothelial injury, reduced cholesterol 7-α hydroxylase which is controlling enzyme of cholesterol catabolism to bile acid, altered apolipoprotein metabolism, and through the action of cortisol which is elevated in the blood of the scurvy as shown in Fig. 5.
Ascorbic acid may concern to platelet function. Addition of ascorbic acid to platelet rich plasma induced inhibition of platelet agglutination and decreased endoplatelet malondialdehyde concentration as reported by Cordova et al. Beetens and Herman reported that ascorbic acid enhanced 6-oxo-prostaglandin F_2α production by protecting the cyclo-oxygenase and PGI-synthetase.
Ascorbic acid might collaborate with tocopherol as superoxide scavenger as shown in Fig. 6 and protects from tissue injury of free radical or lipid peroxides. These findings supports that ascorbic acid has beneficial effects in anti-atherogenesis. Gey calculated antioxidant potential from plasma concentration of ascorbic acid, tocopherol, selenium and β-carotine, and he found the potential was low in the people of the countries with high CHD mortality.
Marginal deficiency of ascorbic acid is not uncommon even in the developed countries. Arround 11% of the serial outpatients in the department clinic showed low plasma level less than 0.5mg/dl (see Fig. 8). This marginal deficiency might be a risk factor for CHD. It may conclude that even minor dietary components have obvious contribution in protection of atherosclerosis, or in some components like vitamin D as reported by Knox have promoting effects on atherogenesis through various biochemical or biophysiological processes which concern to the genesis of atherosclerosis.

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Lipid and energy metabolism was investigated in the aorta and brain microvessels to clarify the mechanisms of the formation of atherosclerosis or angionecrosis.
The aorta had fairly high enzyme activities to hydrolyze or synthesize lipids in lysosomes and microsomes. These enzyme activities were affected by hypercholesterolemia but not by hypertension. In the hypercholesterolemic rabbits cholesterol esterase activity was not increased whereas acyl-CoA: cholesterol acyltransferase activity was 38 times higher than in the control. These results suggest aortic enzyme activities changed in the direction to accumulate cholesterol ester. The aorta had a low activity of fatty acid oxidation and was not affected by hypertension.
Brain microvessels had higher enzyme activities to hydrolyze or synthesize lipids than the aorta. However, these enzyme activities were not affected either by hypercholesterolemia or by hypertension. Brain microvessels had high activities of fatty acidand glucose oxidation. These oxidation activities were decreased as a function of the persistence of hypertension. At the same time mitochondria of smooth muscle cells in brain microvessels were damaged in hypertension. These phenomenon were considered to be an early change of angionecrosis.
Above results suggest that the aorta and brain microvessels had different metabolic properties, i. e., “esterifying” in the former and “oxidizing” in the latter, and that this difference explains in part the formation of different vascular injuries such as atherosclerosis and angionecrosis in response to hypercholesterolemia and hypertension.

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Platelet aggregation, circulating platelet aggregates (ratio), red blood cell deformability, plasma prostanoid (6-keto-PG F_1α, TX B₂), glycosylated hemoglobin, plasma lipids, plasma apoprotein, plasma anti-thrombin III, plasma fibrinolytic activity and calf blood flow were measured in patients with atherosclerosis and non-atherosclerotic controls to clarify the regional differences in atherosclerosis.
The group I serving as the control consisted of 86 men of the average age 50.9 years, the group II consisted of 60 men of the average age 69.0 years and with ischemic heart disease, the group III consisted of 43 men of the average age 68.0 years and with cerebral infarction, the group IV consisted of 12 men of the average age 69.3 years and with atherosclerosis excluding cardiac and cerebral regions, and the group V consisted of 16 men ofthe average age 69.6 years and with more than two regions of atherosclerosis of cardiac, cerebral and the other.
In patients with atherosclerosis (group II, III, IV and V) platelet function was enhanced, plasma total cholesterol was increased, apoprotein A-II was decreased and calf blood flow was also decreased compared to group I. Platelet aggregation, red blood cell deformability, and plasma fibrinolytic activity were increased in group III, and calf blood flow, plasma apoprotein A-I and A-II, plasma 6-keto-PG F_1α were decreased in group III compared to group II. In group IV arachidonic acid-induced platelet aggregation and plasma fibrinolytic activity were increased remarkably compared to any other group. In group V TX B₂ was increased remarkably compared to any other group. By multiple regression analysis, in group II circulating platelet aggregates (ratio) showed a significant correlation with calf blood flow, and in group III ADP-induced platelet aggregation showed a significant correlation statistically.

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This study was undertaken to examine the effect of hypercholesterolemia on contractile response of arteries to several vasoactive agents and transmural electrical stimulation. The isolated descending aorta, coronary and basilar arteries from 10 controls (C) and 6 hypercholesterolemic rabbits fedwith 1% cholesterol diet (CD) for 3 months, were cut into helical strip. The artery was suspended in tissue bath filled with oxygenated Krebs-Ringer solution and kept in 37°C. The strip was attached to force displacement transduser for recording the isometric force.
Contraction-developed tension to KCl, norepinephrine (NE), 5-hydroxytryptophan (5-HT), prostagrandin F_2α (PG) and histamine (His) was determined.
Maximum tension developed by KCl, NE, His was elevated in the basilar artery from CD rabbit (see Table 2). Median effective concentration (ED 50) for 5-HT was higher in the artery from CD rabbit. On the other hand, aorta from CD was supersensitive to His as demonstrated low ED 50. The results were shown in Table 3.
Tension developed by transmural electrical stimulation and passive tension were reduced in the aorta and the basilar artery from CD rabbit.
Responce to vasoactivators were somewhat different by site of arteries obteined. Maximum tension was as following order in both control and CD rabbit. Aorta; NE>His>KCl>PGF_2α>5-HT, coronary artery; His>PGF_2α>KCl>5-HT>NE, basilar artery; His>KCl>5-HT>NE>PGF_2α.
Influences of hypercholesterolemia to tension development by vasoactivators were similar in the three segments of the different parts.
Reduction of passive tension in arteries from CD rabbit revealed the loss of elasticity in CD rabbit arteties.
It may conclude that hypercholesterelemia induced supersensitivity to His and the change of response to vasoactivators of the arteries from hypercholesterolemic rabbits are due to the change of receptor function to vasoactivators and loss of elasticity due to ahterogenic process.

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Arteriosclerosis was classified by the pathological study, but not due to the clinical examination. The purpose of the study is to develop the noninvasive methods for the clinical diagnosis of arteriosclerosis and to evaluate the relation of arteriosclerosis diagnosed by these methods to the arteriosclerotic vascular diseases such as coronary heart disease (CHD), cerebrovascular disease (CVD) and atherosclerosis obliterans (ASO).
The 291 in- and out-patients of both sexes aged 21 to 88 years inclusive of 83 CHD, 48 CVD, 41 ASO and 30 familiar hypercholesterolemic patients (FH), who were visited NCVC-Hospital, were investigated the severity of arteriosclerosis. The calcification index (C. I.) and the wall thickening and stenosis index (S. I.) were calculated from the computed tomography (CT) of the abdominal aorta (AA) and the common iliac artery (CIA) before and after the enhancement with 76% urographine. The C. I. and the S. I. of the AA were highly correlated with those of the lower part of the abdominal aorta (LAA) defined as the upper part within 4 cm of the aorto-iliac bifurcation, (r=0.957, n=54 and r=0.945, n=48) respectively. The C. I. of the LAA was also correlated with that of the CIA. (r=0.721, n=111)
The pulse wave velocity of the aorta (PWV) and ocular fundi were examined in a majority of patients on the same opportunity. Significant correlations between the C. I. and the S. I. of the LAA, (r=0.557, n=224) the C. I. of the LAA and the PWV (r=0.435, n=202) and the S. I, of the LAA and the PWV (r=0.224, n=177) were seen, but the grade of retinal arteriosclerosis was not correlated with the C. I., the S. I. or the PWV. Among the same age group, the most obvious personal variation and the remarkable difference between the arterioscleritic vascular disease (ASVD) and the non-vascular disease (NVD) groups appeared in the S. I. of the LAA, while no significant difference between the ASVD and the NVD groups was observed, in the PWV. Fifty-two per cent in the ASVD group, 25% in the male NVD group and 18% in the female NVD group showed higher value over 40 score of S. I., on the contrary, all CVD patients with 0 score of the S. I. had the retinal arteriosclerosis, as well as 5 of 7 vasospastic CHD patients got O score of the S. I. and the relative higher value of the C. I. compared with that of the S. I. In the FH group, high score of 52.7 of the S. I. but the normal PWV of 678 cm/sec were observed.
In conclusion, (1) the severity of atherosclerosis was diagnosed by the S. I. of the LAA, which might be the best predictable sign for the atherosclerotic vascular disease. (2) The C. I. would be useful for the diagnosis of Monckeberg's sclerosis or atherosclerosis when compared with the S. I. (3) Arteriolosclerosis could be assessed partly by the retinal findings. (4) The PWV would appear the change of the connective tissue of arteries due to the aging, the chronic inflammation and the other causes, but not the index of atherosclerosis.

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The study examined the progresses of a coronary arterial disease among medical, surgical and PTCA treated groups and compared the long-term results with anti-platelet therapy (trapidil 300mg/day or persantin 75mg+aspyrin 300mg/day) or Ca²⁺ channel blockade (nifedipine 40mg/day) groups. 323 patients with effort angina were studied. These were grouped into Group I (96 patients treated medically), Group 11 (147 patients who underwent CABG) and Group III (84 patients treated with PTCA). Group I was further divided into 3 subgroups; I-B 37 cases who were administered with anti-platelet drug for a long period of time, I-C 21 cases who were administered with Ca²⁺ channel blockade and I-A 38 cases with whom none of the 2 drugs was administered. Group II was likewise divided into 3 subgroups of II-B, anti-platelet administered group, II-C, Ca²⁺ channel blockade administered group and II-A, non-administered group. The observation was conducted in 3 to 60 months (average 12.4 months) after the 1st CAG. Serial CAG were taken in each case. The standard of the progress diagnosis was based on Kramer's criteria. RESULTS & CONCLUSION: 1) Among I-A group patients, progress, non-progress, and regress cases were, 50, 40 and 5%, respectively. 55% of the patients showed progress had the effect within 12 months. The level of progress after this period co-relates to the length of observa-tion period, showing 72% peak in over 2 yrs. Relationship with affected vessels; Progress of the responsible coronary arterial vessel with patients involving single vessel disease showed the highest record. The highest rate was with the cases where the disease progressed to a complete occlusion (type 1). On the other hand, among B and C groups, the rate of progress after 2 yrs remarkably became low (p<0.01). LV function was favorable both with I-B, I-C groups. With II-A group, the rate of progress was high in non-grafted vessels within one to one year and a half period with high ratio of type 1, while with II-B, II-C groups, a difference in progress was observed. Among B group patients progression and regression were 33, and 13% within 12 months. While, among C groups, progression, non-progression, and regression were 35, 44 and 21%. 2) Among Group III, 9 cases or 13% showed recurrence of the initially dilated vessel. Of these, 56% showed a significant progress in initally dilated vessel; however, a good result was observed after the 2nd PTCA. 3) These drugs were considered as preventing the progression of coronary artery disease. It is concluded that for angina pectoris patients, a specific treatment program should be established to prevent the progress of the disease, in addition to a conventional therapeutical program. 4) Synergistic effects of these drugs might be resulted from vascular injury suppression, platelet inhibition, coronary vasodilation, improvement of lipids metabolism as well as improvement of LV performance.

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Familial hypercholesterolemia (FH) is an autosomal dominant disease characterized by hypercholesterolemia, tendon xanthomas and premature coronary heart disease. In this paper we report characteristics of coronary heart disease in patients with FH.
Causes of death in 5 homozygous patients with FH were congestive heart failure (n=2) and sudden death (n=3). Their average age of death was 26±11 years (mean+SD). Average serum cholesterol and triglyceride levels were 726±123 mg/dl and 206±66 mg/dl, respectively.
Causes of death in 36 heterozgous patients with FH were myocardial infarction (n=16), sudden death (n=9) and death after coronary A-C bypass surgery (n=1). Thus, “cardiac death” was observed in 26 patients (72%). Average age of death was 66±8 years in males and 66±8 years in females. Their serum cholesterol levels were 368±63 mg/dl in males and 378±76 mg/dl in females.
Coronary angiographic examinations showed coronary stenosis in all the three homozygotes performed coronary angiography. Two homozygotes showed supravalvular aortic stenosis and one homozygote showed coronary ectasia.
Coronary angiographic comparisons were made of the extent and severity of coronary artery disease in 61 heterozygotes with FH and 279 patients without FH. The incidences of coronary stenosis and myocardial infarction were significantly higher in the FH compared to the non-FH. In addition, coronary ectasia also was observed more frequently in the FH than in the non-FH. There were no significant differences in coronary heart diseases between male and female FH patients.

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We studied electron microscopically vascular lesions of lenticulostriate artery and subcortical artery of the front lobs in autopsied brains with hypertensive disorders such as cerebral hemorrhage, 15 cases, cerebral thrombosis or infarction, 5 cases and Binswanger's disease, 6 cases. Diffuse medial cell damage (exhausted degeneration) is an essential alteration regardless association of atherosclerotic intimal thickening. Small arteries, 100-200μ in diameter distributed in subcortical white matter in patients with Binswanger's disease were mostly patent regardless atherosclerosis, and were involved by severe medial cell damage (moth-eaten atrophy and cell necrosis). Those arteries seem to be insufficient on responce to vascular autoregulation mechanism by vascular autonervus and/or vasoactive agents, PGI₂ and TXA₂. Thus, dysfunctional ischemia may occur as a progression mechanism of angiopathic dementia.

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Arachidonic acid (AA) is well known to be metabolized to thromboxane (TX) A₂, 12-hydroxyheptadecatrienoic acid (HHT) and 12-hydroxyeicosatetraenoic acid (12-HETE) in platelets. Prostaglandin endoperoxides and TXA₂ are known to be potent aggregating agents. On the otherr hand, the labile 12-lipoxygenase metabolite, 12-hydroperoxyeicosatetraenoic acid (12-HPETE) has been reported to have a rather anti-aggregating action.
It has been reported that eicosapentaenoic acid (EPA) has a potent inhibitory effect on platelet aggregation. TXA₃ produced from EPA is nonaggregating agent. Although major metabolites of EPA in platelets is said to be those of 12-lipoxygenase pathway, the effect of them has not been clearly elucidated yet. So, we examined the effect of 12-lipoxygenase metabolites of EPA on platelet function and compared them with those of AA.
Both of the labile 12-lipoxygenase metabolites, 12-HPETE and 12-hydroperoxyeicosapentaenoic acid (12-HPEPE) suppressed dose-dependently platelet aggregation and release of 5-hydroxytryptamine (5-HT) induced by collagen and AA, while 12-HETE and 12-hydroxyeicosapentaenoic acid (12-HEPE) had no such effects. The inhibitory effects of these 12-hydroperoxy compounds on platelet aggregation and release reaction seem to be almost equipotent. However, 5- and 15-hydroperoxy isomers were less potent in inhibiting aggregation.
These results may indicate that 12-HPETE and 12-HPEPE have a potent anti-aggregatory activity and may play a role in regulating platelet aggregability.

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Platelet aggregation, circulating platelet aggregates (ratio), plasma β-thromboglobulin, plasma prostanoid (6-keto-PG F_1α, TX B₂), plasma apoprotein and plasma sialic acid were measured in patients with atherosclerosis and non-atherosclerotic disease, e. g, chronic obstructive pulmonary disease, and in healthy subjects to clarify the significance of platelet function and plasma prostanoid in atherosclerosis.
The group A serving as the healthy subjects consisted of 33 men of the average age 41.5 years, the group B consisted of 214 men of the average age 67.6 years and with ischemic heart disease and cerebral infarction in chronic state, and the group C consisted of 106 men of the average age 62.3 years and with non-atherosclerotic disease, mainly chronic obstructive pulmonary disease.
In the group B ADP-, collagen-, adrenaline- and arachidonic acid-induced platelet aggregation and circulating platelet aggregates were significantly enhanced compared to both the group A and the group C. As for plasma β-thromboglobulin, there was no significant difference between the three groups. Plasma apoprotein A-I was significantly increased in the group C compared to both the group A and the group B. Plasma sialic acid was significantly increased in the group B compared to both the group A and the group C. Significant positive correlation of TX B₂ to β-thromboglobulin and significant negative correlation of 6-keto-PG F_1α to apoprotein B were found in group B.
These results suggest that the enhancement of platelet function may play a role in atherogenesis with relation to the prostanoid production, plasma apoprotein and sialic acid.

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Previous studies suggest a role for sialic acid on platelet function. It was shown in such clinical syndromes as Bernaud-Surlier syndrome and Thromboasthenia. Platelets from those patients are known to be reduced sialic acid or lack of a certain glycoprotein (GP1-b). On the other hand increased glycoprotein or sialic acid were shown in some thrombogenic state (during ingestion of oral contraceptive drug and estrogen therapy for prostatic cancer patient).
It was known that almost those glycoprotein have sialic acid on out side of platelet membrane and give a negative charge to the platelet membrane and affect platelet function. We examined platelet sialic acid and sialidase activity (EC3. 2. 1. 18) in arteriosclerotic rat in order to clarify the relationship between arteriosclerosis and sialic acid change in platelet. At first we confirmed tipical atherosclerotic lesions with atheroma and carcification in aorta using H-E stein, von Gieson stein, Sudan stein and Kossa stein methods.
We performed glucose tolerance test, thyroid function test and lipid analysis. In this experimental rat showed abnormal glucose tolerance test with low responce of insulin and hypothyroid state due to intake propylthiouracil in experimental diet. Plasma sialic acid was slightly elevated in arteriosclerotic rat compaired with normal control rat but not statistically significant. Platelet sialic acid was significantly increased in arteriosclerotic rat. Platelet sialidase activity was significantly decreased in arteriosclerotic rat.
This data suggest that changes of sialic acid and sialidase activity may play a role on platelet function and accerate arteriosclerosis. But it was not clear wether this change of platelet sialic acid in our experiment was the result of angiopathy or primary metabolic disorder in this experimental condition.

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Recombinant clones containing cDNA sequences coding for human Apo-E have been isolated from a human adult liver cDNA library. The library was constructed by the Okayama-Berg method and screened with the oligonucleotide probe which corresponds to Apo-E amino acids 218 to 222 (Met-Glu-Glu-Met-Gly). Nine Apo-E clones were obtained and the plasmids were digested with Pst1. The longest cDNA insert named pAPOE7 was sequenced using the Sanger technique, revealing that it corresponds to the known Apo-E DNA sequence 523 to 666 base pair. Genomic DNAs were obtained from peripheral leukocytes and cultured skin fibrobrasts and analyzed using Southern blotting methods. The pAPOE7 was nicktranslated and used as a probe for hybridization. A patient with Apo-E absence and normal controls were analyzed. In the present study the Apo-E gene is present in the patient with Apo-E absence.

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The aim of this study is to determine the relationship between apolipoprotein (apo) E phenotypes and plasma lipid, lipoprotein and apo E levels in young (mean, 21.2 years of age) haelthy subjects. Apo E phenotypes were determined by a rapid flat gel isoelectric focusing method as we had developed. The young subjects with apo E 3/2 had significantly higher levels of plasma triglyceride (TG), VLDL-TG and VLDL-cholesterol (VLDL-C) than those with apo E 3/3, and in addition showed a tendency to have higher levels of plasma apo E and VLDL-C/VLDL-TG ratio, but it was not significant. The young subjects with apo E 4/3 had also significantly higher levels of plasma TG, VLDL-TG and VLDL-C than those with apo E 3/3. One subject with apo E 4/2 was observed in this study, who had the highest levels of plasma TG and VLDL-TG. These results indicate that apo E phenotype E 3/2, E 4/3 and E 4/2 are associated with lipid abnormalities which may be caused by abnormal functions of apo E2 and E4 even in the young subjects. It is concluded that plasma TG and VLDL-lipid levels in young subjects may by, at least in part, genetically controlled through apo E phenotypes.

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To test the relation between apo E phenotypes and atherosclerosis, apo E phenotypes in very low density lipoprotein (VLDL) in 330 hyperlipidemics including 55 familial hypercholesterolemia (FHC) and 56 normolipidemic subjects were analysed by isoelectrofocusing method.
The frequency of three major apo E phenotypes in normolipidemics is as follows: E 3/3-69%, E 4/3-18%, E 3/2-5%. The frequency of apo E phenotypes in type II hyperlipidemics was almost the same as that of normolipidemics. In type IV hyperlipidemics, the frequency of E 4/3 was increased to 39%, and the freequency of E 3/2 was increased to 9%. Among type II, III and IV hyperlipidemics other than FHC, increases of serum triglyceride, VLDL-triglyceride and VLDL-cholesterol were observed in E 4/3 and E 3/2. This tendency was remarkable in type III and IV hyperlipidemics. There was no difference in serum lipids of FHC among three major apo E phenotypes. Serum apo E level in E 3/2 (10.1±2.4mg/dl) was significantly higher than that of E 3/2 (6.8±3.4mg/dl) or E 4/3 (6.7±4.0mg/dl).
It was suggested that there was the correlation between apo E phenotypes and serum lipoprotein lipids or serum apo E levels. Analysis of apo E phenotypes is considered to be useful in understanding the pathogenesis and clinical significance for dyslipoproteinemic diseases.

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Liver has two distinct lipoprotein receptors; one is apolipoprotein (apo) B, E receptor and the other is apo-E receptor. We partially purified apo-E receptor protein from solubilized rat liver membranes using ion exchange chromatography and preparative gel electrophoresis.
Rat liver membrane was prepared by ultracentrifugation as the 8, 000 to 100, 000×g pellets after the homogenation. The liver membrane was solubilized in the presence of 40mM octylglucoside. Ligand blotting of the solubilized liver membrane protein, using HDLc as a ligand, revealed that two bands were visualized besides that of the apo-B, E receptor. Molecular weights of these proteins were estimated to be about 60K and 36K on 14% SDS-PAGE. The 36K protein was separated from the apo-B, E receptor protein using preparative gel electrophoresis. The binding of ¹²⁵I-HDLc to the isolated 36K protein showed a saturable manner, and was inhibited only by HDLc competitively but not by human LDL and canine HDL. These findings suggest that the 36K protein is the apo-E receptor.

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Arteriosclerotic changes in 181 aortas and 84 coronary arteries of Japanese under 40 years of age, which were autopsied during recent 5 years, were observed macroscopically and microscopically. Relationship between age, sex, intimal thickening and the contents of elastin, collagen, and smooth muscle fiber in the aorta and coronary arterial media were also investigated.
Surface involvement (SI) and atherosclerotic index (AI) showed more extensive involvement in the female at 20 years of age, and after 20 years, SI and AI of female decreased. On the other hand, SI and AI of male gradually increased from 0 year to 40 years of age.
In accordance with SI, AI and intimal thickening, medial content, especially collagen content better correlated to that of female at 20 years of age. This phenomenon suggests that the collagen content may play an important role in pathogenesis of arteriosclerosis of aorta in children and young adults.

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The abdominal aorta-inferior mesenteric artery branchings of 65 human subjects younger than 39 years old were examined at autopsy to study the mechanical effect of the blood flow on the localization of early atherosclerotic lesions and their precursors.
(1) At the apex of the flow divider, the apical pad, a thin but extremely fibrous fibrocellular intimal thickening, was almost always observed, even from subjects younger than 1 year old. However, no atherosclerotic lesions were found here even in the subjects older than 30 years.
(2) At the proximal wall of the bifurcation, the proximal pad was observed after around 10 years old. This was a sparse fibrocellular intimal thickening in abundance of smooth muscle cells and oedematous extracellular ground substance accompanied by various degree of abnormalities of elastic tissues, such as fragmentation, thinning, and duplication. In the subjects older than 10 years, an extensive lipid deposition was almost always observed in the intima at the bottom layer of the intimal thickening. The lipid deposition was found extracellularly at the early stage, and intracellularly at the late stage. The foamy cells were frequently found in this portion. This type of fibrocellular intimal thickenings were, therefore, thought to be potential to develop into the atherosclerotic plaque.
(3) From the fluid mechanical view points, the apical portion of a branching is considered to receive a high wall shear, whereas the proximal portion of the branching to have a low wall shear, or sometimes even a flow separation. These mechanical factors are concluded to play a major role on the differentiation of the fibrocellular intimal thickenings through a modification of the elastic tissues in the intima. Of them., the proximal-padtype of fibrocellular intimal thickening is thought of as the early atherosclerotic lesion at this branching, so that its specific localized patterns in the human abdominal aorta result.

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The effects of mild aerobic exercise on serum lipids and apolipoproteins were studied in 24 patients with essential hypertension. An approximately 50% of maximal oxygen uptake (VO_2max) which was predetermined from blood lactate threshold for each individuals has been enployed as a training intensity. They were trained by bicycle ergometer for 60min at a time, three times weekly for 10 weeks. Significant reduction in both systolic and diastolic blood pressures and increased work intensity at blood lactate threshold were observed. The HDL-cholesterol was increased significantly at 4th and 7th week following exercise. Apo A-II was significantly increased at 4th and 10th week. Also, HDL-C/TC ratio was significantly improved at 4th and 10th week and Apo B/A-I ratio was significantly improved at 7th and 10th week. No significant changes were observed in total cholesterol, Apo A-I, Apo C-II, Apo C-III, Apo B and Apo E levels. These data suggest that mild aerobic exercise not only depress blood pressure but also improve lipoprotein status.

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Apolipoprotein (apo) A-I and A-II distributions in lipoproteins (LP) and bottom fractions (BF) above d. 1.21g/ml were investigated in hemodialysis pstients (HD) and in age-matched healthy controls (C).
1) Serum apo A-I and A-II levels were significantly lower in HD than in C, while the apo A-I/II ratio was unchanged between two groups.
2) In the patient group, apo A-I and A-II levels in high density lipoproteins (HDL), particularly HDL₂, and the apo A-I/II ratio of HDL₂ significantly decreased.
3) There was a significant increase in both concentrations and percent distributions of apo A-I and A-II in the BF of the patient group while those of lipids, particularly total cholesterol, showed reverse changes.
4) The changes of LP abnormality in HD were comfirmed by the gel-filtration method.

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We reported that apolipoprotein (apo) B-48 mainly derived from small intestine in human was frequently accumulated in the triglyceride (TG) rich lipoproteins (Lps), such as very low density Lps (VLDL) and intermediate density Lps (IDL), in uremics and the accumulation of apo B-48 was increased at peroral olive-oil load and decreased or disappeared after hemodialysis using heparin as an anticoagulant.
The present study was undertaken to investigate the metabolic difference of apo B-48 between heparin-dialysis and gabexate mesilate (FOY)-dialysis without lipolytic function in hemodialysis patients with apo B-48.
After 12 hr starvation, fasting sera were obtained at 0 and 2hr during regular hemodialysis. VLDL, IDL and low density Lps were isolated by sequential ultracentrifugation and used for chemical analysis on 3.5% polyacrylamide-gel electrophoresis in 0.1% SDS to detect apo B subclasses.
Heparin-dialysis caused a decrease in serum TG, VLDL and IDL levels but not FOY-dialysis. Free fatty acids (FFA) was significantly increased at 2hr later by heparin-dialysis whereas FOY-dialysis at 2hr had only a slight increase in FFA. In patients with normo- or hypo-triglyceridemia, apo B-48 in TG-rich Lps was disappeared by heparin-dialysis but apo B-48 remained unchanged in patients with hypertriglyceridemia. On the other hand, FOY-dialysis did not affect the apo B-48 accumulation regardless of serum TG levels.
These results demonstrated that heparin-dialysis is effective for improving apo B-48 accumulation in TG-rich Lps by lipolytic function together with the removal of uremic toxins in hemodialysis patients.

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Fatty acids of plasma lipids from subjects at 2 weeks or 2 years after myocardial infarction and from age-matched controls were analyzed. The proportion of oleate (18: 1) in plasma cholesterol ester (Cho E) was higher in the myocardial infarction patient and the 18:1/18:2 (linoleate) ratio of plasma Cho E was positively correlated with either free Cho level or with triacylglycerol level. The selectivity of plasma lecithin: Cho acyltransferase (LCAT) for the endogenous lecithin species was determined to be in the order of saturated>>monoene>diene>tetraene>>pentaene plus hexaene species, which was quite different from that reported earlier. The molecular species of plasma Cho E were found to be the complete reflection of molecular species of Cho E produced by the LCAT, suggesting that the contribution of acyl CoA: Cho acyltransferase (ACAT) to plasma Cho E formation was negligible under the conditions examined.

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Extremely high levels of total cholesterol in serum were observed in two patients with hepato-cellular carcinoma (H. C. C.). The maximum levels of total cholesterol were 876mg/dl in patient 1, and 531mg/dl in patient 2.
We measured the cholesterol levels of each lipoprotein fraction and serum apolipoprotein levels in H. C. C. patients with hypercholesterolemia (patient 1, 2), H. C. C. patients without hypercho-lesterolemia (patient 3-11), and normal controls.
Serum VLDL- and LDL-cholesterol levels in H. C. C. patients with hypercholesterolemia were much higher than those in H. C. C. patients without hypercholesterolemia and normal controls. However, serum HDL²- and HDL³-cholesterol levels in H. C. C. patients were lower than those in normal controls. These results suggest that the increase of total cholesterol in H. C. C. patients is attributed to the increase of VLDL- and LDL-cholesterol.
Serum apolipoprotein B and E levels in H. C. C. patients with hypercholesterolemia were much higher than those in H. C. C. patients without hypercholesterolemia and normal controls. However, serum apolipoprotein A-I and A-II levels in H. C. C. patients were much lower than in normal controls. Serum apolipoprotein C-II and C-III levels in H. C. C. patients with hypercholesterolemia were higher than those in H. C. C. patients without hypercholesterolemia. Apolipoprotein B is protein component of LDL and apolipoprotein B, C, and E are rpotein components of VLDL. These suggest that VLDL and LDL particles increase in H. C. C. patients with hypercholesterolemia.
The biliary obstruction by the tumor was absent in the two H. C. C. patients with hypercholesterolemia. This suggests that the raised serum cholesterol levels are associated with increased synthesis of VLDL and LDL particles.

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In the present study, a sensitive assay technique for determining AT III related antigen (AT III RA) was developed, and the urinary excretion rate of AT III RA was examined in cerebral stroke. The excretion rate of AT III RA in cerebral hemor-rhage (CH) increased significantly.
The patients with CH were further classified into two group depending on their state of consciousness.
The difference between the deteriorated group and the alert group was statistically significant.
The excretion rate of AT III RA in cerebral thrombosis (CT) was significantly lower than that in CH (p<0.001).
The excretion rate of AT III RA in both CH and CH was significantly higher than that in the healthy control group.
Thus, the results obtained indicate that the excretion rate of AT III RA may change dynamically in cerebral stroke.

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When the diagnosis of acute cerebral vascular disease is made, CT scan of the brain and other medical instruments, such as NMR or positron CT, have recently become very useful. However, the measurement of enzyme activity in serum, such as creatine phosphokinase and aldolase, is not always useful in such disease. Therefore convenient enzymatic diagnosis of cerebral vascular disease is requested in primary care. We examined CPK isoenzynee of patients who had suffered from acute cerebral infarction and found atypical band at the negative pole side of MM band. As we suspected it was adenylate kinase which is well known as myokinase, we measured it in healthy adults and patients with acute cerebral infarction. The activity of it is the highest in skeletal muscles but it also existed in the brain. The enzyme activity was measured by the decrease of NADH through the production of ADP.
The obtained results were as follows: The normal serum adenylate kinase levels were lower than 5mU/ml and the activity in patients with acute cerebral infarction was, on average, 18.79mU/ml. Furthermore the activity of it increased in the early days of cerebral infarction and then decreased gradually. In addition to, we made cerebral infarctions in rabbits experimentally and measured serum AK levels. The activities of AK in serum increased immediately after the treatments in some of them and continued on a high value until the 5th day after onset. But those of the other animals increased gradually after the treatment. Namely it was observed that the measurement of serum adenylate kinase may be useful in the diagnosis of acute cerebral infarction.

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Effects of trapidil on lipoprotein abnormalities in survivors of cerebral infarction (CI) were studied. A 300mg daily dose of trapidil was administered orally to 1.0 inpatients and 19 out-patients with CT for 3 months.
Before and after the administration of trapidil, plasma concentrations of cholesterol (TC), triglyceride (TG), high-density-lipoprotein cholesterol (HDL-C) and cholesterol in HDL subfractions (HDL₂-C and HDL₃-C) were measured in both patient groups, and the concentrations of apolipoproteins (Apo A-I, A-II, B, C-II, C-III, E) were measured in outpatients.
TC and TG concentrations were determined by enzymatic methods, HDL-C by the heparin-Ca⁺⁺ precipitation method, and HDL₂-C and HDL₃-C by the polyacrylamide gel electrophoresis method. Apolipoproteins were determined by a single radial immunodiffusion method.
TC and TG concentrations were unchanged in both groups. HDL-C increased significantly in inpatients, and tended to increase in outpatients. With regard to the HDL subfractions, the HDL₂-C concentration increased significantly, whereas the HDL₃-C concentration increased slightly in inpatients and remained virtually unchanged in outpatients. Apo A-I concentration tended to increase, whereas apo B concentration decreased significantly. As a result, the ratio of apo B to apo A-I decreased significantly.
These results suggest that trapidil is beneficial in the treatment of lipoprotein abnormalities in patients with cerebral infarction.

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The observation of metabolic process in LDL formation from VLDL is one of important problems to elucidate lipoprotein metabolism with regard to atherosclerotic changes. The hydrolysis of VLDL triglyceride elicited by lipoprotein lipase is the most noticeable phenomenon in this metabolic process. Apolipoprotein C-III (apo C-III) has been shown to be an inhibitor of lipoprotein lipase activity in competition with apo C-II. This study was intended to clarify the significance of serum apolipoprotein C-III in cerebrovascular disorders by observing fasting serum apo C-III level in 41 infarct and 14 hemorrhagic patients who had stroke 3 months or more previously, and 68 healthy adults. Serum apo C-III level was determined by single radial immuno-diffusion method using agar plate containing specific anti-apo C-III serum. The mean values and standard deviations of serum apo C-III in 11 healthy adults aged 20 to 29 years and in 19 above 60 years were 6.8±1.3mg/dl and 6.6+1.0mg/dl respectively. The values in 41 infarct and 14 hemorrhagic patients were 8.6±2.7mg/dl and 8.1±3.1mg/dl. The level in infarct patients was significantly higher than the value of 6.6±2.3mg/dl in 37 age-matched healthy adults. In subjects with normal total cholesterol and triglyceride concentration, patients' apo C-III level was also higher significantly than the level in healthy adults. The level in patients with good functional capacity was high. In patients, apo C-III was directly proportional to total cholesterol, triglyceride apolipoprotein A-II and C-II, and apo C-III correlated positively with serum albumin and plasma antithrombin III.
The high level of apo C-III in normolipidemic patients detected in present study confirms usefulness of observation of apolipoprotein rather than that of serum lipids in the investigation of lipoprotein metabolism relating to atherosclerotic changes in cerebrovascular disorders. Some significant relations of this apolipoprotein to the indicators of lipoprotein metabolism adopted in this observation are easily understandable. While the relations between apo C-III, serum albumin, and plasma antithrombin III call our attention as new findings in the investigation of athero-thrombotic disorders. High albumin level elicits increase in blood filtrability, and antithrombin III inhibits clotting as well known.
Free fatty acids (FFA) liberated in the hydrolysis of VLDL triglyceride by the action of LPL binding with apo C complex is mostly conjugated with albumin, and non-conjugating FFA promotes thrombus formation. From these facts and high level of apo C-III in patients with good functional capacity, it is concluded that apo C-III regulates FFA liberation from VLDL triglyceride by competition with apo C-II, and inhibits following thrombus formation relating to the occurrence of ischemic lesion in the brain and heart.

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An elevated concentration of lipoprotein (a) [Lp (a)] in the serum has been considered a risk factor for ischemic heart disease by a number of investigators. In the present study, the association of Lp (a) with ischemic heart disease [IHD] or cerebral infarction [CI] within the Japanese populations was investigated.
Lp (a) concentrations were determined in 191 healthy subjects, 143 patients with various diseases excluding atherosclerotic diseases [patient controls], 62 patients with IHD, and 171 patients with CI by the single radial immunodiffusion method.
Patients with CI were divided into two subgroups on the basis of clinical history, neurological signs and findings of CT scan. The two subgroups were CI in the distribution of small perforating artery [CI(P)] and large cortical artery [CI(C)].
The frequencies of elevated Lp(a) levels (15mg/dl or more) were 39.8% in the healthy subjects and 44.8% in the patient controls. Compared to healthy subjects or patient controls, significantly higher frequencies of elevated Lp (a) levels were found in the patients with IHD (66.1%), and in the patients with CI (C) (67.2%), but not in the patients with CI (P) (43.7%).
Age, serum cholesterol levels, and their combinations had no significant influence on the presence of raised Lp (a) concentrations.
The results of this study indicate that Lp (a) represents a risk factor for atherosclerosis of the coronary and cerebral arteries.

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The possibility that some factor in serum changes the substrate specificity of purified human plasma carboxyl esterase, which hydrolyzes the short chain fatty acid ester, tributyrin, was investigated. The purified carboxyl esterase from human plasma hydrolyzed 48mmol of tributyrin/mg of protein/h, monoolein at 1, 550μmol of released fatty acids/mg of protein/h, diolein at 133μmol of released fatty acids/mg of protein/h, and triolein at less than 10μmol of released fatty acids/mg of protein/h. When human serum was applied to phenyl-Sepharose, a triolein hydrolysis-promoting factor (THPF) for purified carboxyl esterase was bound to the gel and was eluted with water. This partially purified human serum THPF enhanced carboxyl esterase-catalyzed triolein hydrolysis about 30-fold, diolein hydrolysis 2-fold, and monoolein hydrolysis 1.5-fold. Hydrolysis of triolein in very low density lipoprotein (d<1.006) and intermediated lipoproteins (1.006<d<1.019) by carboxyl esterase was also enhanced by addition of THPF. THPF activity was reduced by treatment of delipidation, but resistant to trypsin treatment or heating at 50°C. These results indicated that serum carboxyl esterase can hydrolyze the long chain fatty acid ester, triolein, in the presence of triolein hydrolysis-promoting factor in serum.

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PRP is present in chylomicron and d>1.21 fraction of human plasma. PRP was separated from lipoprotein-depleted serum by absorption to Intralipid. Antiserum to PRP was raised by rabbit and the serum concentration was assayed by single immunodiffusion. PRP levels in acute hepatitis and hepatic cirrhosis were lower than controls. PRP levels in fatty liver and nephrotic syndrome were higher. Also PRP levels in ischemic heart disease, diabetes mellitus, cerebrovasculer disease and hyperlipidemia were higher. Furthermore, patients with inflammatory disease had higher PRP levels. These data suggested that liver may be involved in PRP synthesis and possible relation to atherosclerotic disease and inflammatory disease, indicated.

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A simplified intravenous fat emulsion tolerance test (FETT) using 0.25ml/kg body weight of 10% Intralipid^® has been established to evaluate triglyceride rich lipoprotein metabolism. Fractional removal rate (K₂) of FETT and it's reliability were compared to that of intravenous fat emulsion tolerance test using 1ml/kg body weight of 10% Intralipid which is a modification of the method developed by Carlson. Both tests were done on the same 15 subjects within 7 days.
FETT: Fifteen subjects were fasted for 14 hours. Then 0.25ml/kg body weight of 10% Intralipid was injected intravenously in 90 seconds. Time measurements were started at midpoint of injection, and blood was sampled at 5, 7, 9, 11, 14, 17 and 20 minutes, respectively. Light scattering index (LSI) of serum diluted 1:100 in the physiological saline, was determined by nephelometer (Nephelotik DN 2110, Kyoto Dai-ichi Kagaku Co. Ltd.). The zero-time value was subtracted from the value for each post-injection sample. For calculation of fractional removal rate (K₂) of fat emulsion, LSI's were plotted against time in a semilogarithmic plot. Slope of the regression line was determined by method of least squares and equation log Y=bx+a was calculated. The removal rate, K₂, of fat emulsion was expressed as -b. Student's t-value was calculated as b/Sb ratio where Sb is standard error of b.
A modification of method by Carlson:The subjects were given 1ml/kg body weight of 10% Intralipid as intravenous infusion for 10 minutes. Time measurement was started at zero time of injection, and blood was sampled at 15, 20, 25, 30, 35, 40, and 50 minutes, respectively. K₂' and Student's t-value were calculated in the same way as FETT was done. The mean value of K₂ was approximately 2 times higher as compared with that of K₂'. Also, K₂ was higher than K₂' in each subjects, respectively (Fig. 1). There was no significant difference between t-value of K₂ and t-value of K₂' (Fig. 2). K₂ correlated" to K₂' (r=0.78, p<0.001, Fig. 3). It was observed that fractional removal rate was significantly influenced by dose of administered fat emulsion. It may be concluded that FETT is a simple and good tool for study of triglyceride rich lipoprotein metabolism as a modification of method by Carlson.

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Various serum lipid levels (hypo-, normo- and hyper-cholesterolemic) are shown in dys-β-lipoproteinemia (-LP). Though type III hyper-LP (hypercholesterolemic dys-β-LP) is characterized by abnormal lipid composition of VLDL and elevaied level of apolipoprotein E (apo E), diagnosis of normo- and hypo-cholesterolemic dys-β-LP are offenly difficult. At the present study, we established simple and sensitive methods to diagnose dys-β-LP only by measurement of serum apolipoproteins. In purpose to define new approach for diagnosis of dys-β-LP, serum apo B, apo C-II, apo C-III and apo E levels were determined by the method of single radial immunodiffusion. These apolipoproteins were analysed in subjects with dys-β-LP (n=7), hyper-LP (n=67) and normo-LP (n=41). A serum apo E/apo C-III ratio in dys-β-LP was 1.37±0.59 (mean±SD). This value was significantly higher than the ratios among normo-LP (0.45±0.17), type IIa (0.51±0.11), type IIb (0.45±0.17), type IV (0.45±0.13) and type V (0.47±0.22). A serum apo E/apo B (×100) ratio in dys-β-LP was 25.2±10.2. This value was also significantly higher than the ratios among normo-LP (4.4±1.5), type IIa (4.0±0.9), type IIb (4.7±1.9), type IV (7.2±3.1) and type V (15.5±5.9). Based on these data, it is proposed that the apo E/apo C-III ratio of >1.0 was diagnostic value of type III and the apo E/apo B (×100) ratio of >10.0 was also diagnostic value of normo- and hypo-cholesterolemic dys-β-LP. As to determine serum apolipoproteins very simple by single radial immunodiffusion method, the ratios will be useful for diagnosis and detection of dys-β-LP in clinical and epidemiological studies.

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Twelve members of family pedigree of hypo-β-lipoproteinemia were analyzed for lipoprotein compositions, apo B levels by EIA, its isoforms by SDS gel electrophoresis.
Judging from LDL-chol & apo B levels, a 75-year-old proband father who died of unknown fever, thrombopenia, and anemia, and his wife were heterozygous. The father had ataxic movement of hands and gait disturbance in the late life. Three out of 4 alive siblings had deficiency of LDL-chol (<6mg/dl) and LDL-apo B (<2mg/dl). Electrophoresis revealed deletion of apo B-100, but exhibited apo B-48 band in serum obtained after fatty meal in these 3 siblings, indicating homozygous inheritance. Clinically, acanthocytic RBC, fatty liver and low levels of serum vitamin A & D were noted. The other heterozygous sibling had 26mg/dl LDL-chol and 5mg/dl apo-B levels. Seven persons with the 3rd generation showed all low levels of chol (85-140mg/dl), LDL-chol (40-63mg/dl) and apo B (10-20mg/dl). They also showed mild acanthocytosis and a decrease of fatsoluble vitamines.
The present cases are similar to the preveously reported 2 cases with normotriglyceridemic abetalipoproteinemia, but are the first demonstration of selective apo B-100 deletion in homozygous hypo-β-lipoproteanemia.

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We report a new case of Tangier disease in Kochi Prefecture.
A 44-year-old man was admitted to our clinic in August, 1984, because of marked hypocholesterolemia and glycosuria.
He had following clinical features: 1) history of tonsillectomy for the enlarged tonsils; 2) enlargement of the liver and spleen; 3) thrombocytopenia (110, 000/cmm); 4) appearance of foam cells in the bone marrow. Results of the lipid and lipoprotein examinations were as follows: 1) hypocholesterolemia (64mg/dl) and hypertriglyceridemia (272mg/dl); 2) extremely low level of HDL-cholesterol (2.5mg/dl) and decreased ratio of cholesterol to triglyceride (0.58) in LDL; 3) extremely low levels of serum apolipoprotein A-I (less than 1.0mg/dl) and apolipoprotein A-II (1.1mg/dl); 4) relative increase of apolipoprotein A-I isoprotein 2; 5) normal level of apolipoprotein C-III (5.7mg/dl).
In the family study, no parental consanguinity was known. His parents, son and daughter were all found to have HDL-cholesterol levels that average half the normal mean. So they were thought to be heterozygote of Tangier disease.
These clinical and biochemical findings of the patient were consistent with the characteristic features of Tangier disease. However, this patient differed from previously reported cases in several respects.
He had a glycosuria and 75g OGTT revealed overt diabetic. And we observed the increased electrophoretic mobility of the beta-band in agarose after improved diabetic control. Another caracteristic was the slight increase of apolipoprotein A-I isoprotein 6. These findings were not described in most cases of Tangier disease and we considered that these unusual features might be the consequence of complicated lipoprotein metabolism in the patient by the affection of diabetes mellitus on Tangier disease. Regarding the clinical points, no signs of coronary artery disease and neurological abnormalities were observed at present.
In conclusion, he represents the second known family with Tangier disease in Japan.

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In fasting serum of familial lecithin: cholesterol acyltransferase (LCAT) deficient patient, existence of intermediate-dencity lipoprotein (IDL) fraction was observed. Triglyceride (TG) hydrolysis of the IDL fraction by hepatic TG lipase was lower than those of IDL fraction from normal post-prandial serum. That impairment was partially recovered by preincubation of the patient IDL with serum obtained from normal person. So, the impairment was suspected to be caused by an increase in free cholesterol on the surface of IDL particle, which is directly induced by LCAT deficiency in serum. Furthermore decreased activity of hepatic TG lipase in postheparin plasma might be involved in the retention of IDL fractions.

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We recently discovered two homozygous cases of hyper-HDL₂-cholesterolemia associated with premature corneal opacities. Patient 1 is a 55-year-old man, whose serum HDL-cholesterol levels were much elevated to -140mg/dl, while serum total cholesterol was only slightly increased and serum triglyceride moderately reduced. Serum levels of apolipoprotein (apo) A-I and E were also elevated. Patient 2 is a 58-year-old man whose serum HDL-cholesterol was also much increased to 130-169mg/dl. The lipid and lipoprotein patterns of these patients were closely similar by ultracentrifugal analysis and the increase of HDL-cholesterol was attributed solely to the enrichment of cholesteryl ester (CE) in HDL₂ fraction (1.063<d<1.125g/ml). The trait was considered to be inherited in the family of Patient 2. In postheparin plasma, LPL activities were increased in these patients, whereas H-TGL showed reduced activities. In order to elucidate the mechanism of accumulation of CE in HDL₂, we examined CE net transfer rate according to the modified method of Fielding et al. In control subjects there was a net mass transfer of CE from HDL to VLDL and LDL after a 1hr's incubation with DTNB at 37°C, while in both cases there was a net transfer of CE in the opposite direction leading to the accumulation of CE in HDL.
We also examined the effect of probucol on the lipoprotein and apoprotein levels of these patients. Probucol reduced serum levels of HDL-cholesterol, apo A-I and apo E parallel to the reduction of serum total cholesterol. The decrease of HDL-cholesterol was largely due to the reduction of cholesterol in HDL₂ fraction. Examination of patients' sera by HPLC disclosed that large HDL₂ particles became smaller to almost normal sizes after the treatment with probucol and that the change was proved to be reversible after stopping administration of the drug.
We also examined CE net transfer rate after treatment with probucol, and found that the reversion of CE net transfer was normalized in both cases after the therapy. We therefore conclude that abnormalities in CE net transfer might be involved in the pathogenesis of hyper-HDL₂-cholesterolemia.

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A 55-year old male with homozygous familial hypercholesterolemia is described. His plasma cholesterol concentration was 540mg/dl. His parents of a consaguineous marriage, brothers and a sister also had mild hypercholesterolemia. Tendinous and tuberous xanthomas had appeared since he was 10-year old. Recently angina pectoris on efforts turned out and an electrocardiogram showed myocardial ischemic damage. A coronary angiogram revealed diffuse coronary arterial narrowing, although it has been reported that strictures are commonly seen in the proximal portions of the coronary arteries but the distal vessels are remarkably free of disease in familial hypercholesterolemic homozygotes. Usually familial hypercholesterolemic homozygotes die from myocardial infarction before age 30, this patient is 55-year old and the most long-lived as far as we surveyed. The receptor studies revealed that the fibroblasts of this patient bound as much LDL as normal cells, but they could not mediate internalization of receptor-bound LDL and degradation of LDL was negligible. So this case is the fourth case of homozygous familial hypercholesterolemia mutant with a defect in internalization.

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Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by marked hypercholesterolemia, tendon xanthomas and premature coronary heart disease (CHD). It is generally accepted that FH is a very atherogenic disease, since homozygous FH is often accompanied by myocardial infarction before age 30 and even in its heterozygous form CHD becomes manifest at an earlier age than in normal subjects. However, serum cholesterol levels in patients with heterozygous FH are not always parallel to the severity of CHD and there must be other factors affecting the development of CHD in FH. Eighty-three subjects with heterozygous FH aged over 30 years were included in this study. The incidence of CHD became higher with their age in both sexes, and especially in female patients CHD became manifest over 50 years of age. Patients were subdivided into two groups in each sex with and without CHD, and we then compared between each group as to LDL receptor activities, serum lipids and lipoproteins, as well as clinical parameters such as Achilles tendon thickness (ATT), blood pressure and the incidence of corneal arcus, xanthelasma and tuberous xanthoma.
There was no significant difference in serum total cholesterol levels between two groups with and without CHD in both sexes, whereas serum HDL-cholesterol levels were significantly lower and atherogenic indices significantly higher in both sexes in CHD (+) group than in CHD (-) group. Serum triglyceride levels were higher in CHD (+) group especially in males and ATT tended to be thicker in CHD (+) group in both sexes. There was no significant difference between the two groups in blood pressure and the incidence of xanthelasma and corneal arcus, although tuberous xanthomas were more frequently seen in CHD (+) group.
In fifty-one subjects (30 males and 21 females), we determined LDL receptor activities of skin fibroblasts according to the method of Goldstein et al. Even in FH-heterozygotes, there were wide variations in the LDL receptor activities, which negatively correlated with the level of serum total-and LDL-cholesterol levels. There was a tendency that LDL receptor activities were relatively lower in CHD (+) group than in CHD (-) group, but there was some cases with CHD whose LDL receptor activities were relatively high.
We also referred to atypical two cases of FH with elevated serum cholesterol levels and Achilles tendon xanthomas, and these traits were considered to be inherited in this family. However, LDL receptor activities (binding, internalization and degradation) of these cases were higher than those of normal controls in several determinations and they showed no clinical signs of CHD. Abnormalities in LDL receptor proteins have recently been classified by Goldstein & Brown at a molecular level, therefore the impaired locus of these cases must further be elucidated, but at present we include these cases in the category of FH.

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Two male heterozygous familial hypercholesterolemia were treated by repeated Plasma Exchange (PE) at intervals of 3 weeks for a year. One was 57 and another was 51 years old whose initial plasma cholesterol level were 490 and 442mg/dl, respectively. Both patients had angina pectoris and their plasma cholesterol were resistant to the conventional drug treatment. PE was performed using IBM cell separator (model 2997). Plasma (1, 500ml) was removed and replaced by an equal volume of human serum albumin. It is well known that apolipoproteins play an important role in regulation of lipoprotein metabolism. However, changes of plasma appolipoproteins concentrations during long-term PE for familial hypercholesterolemia have not been reported. Apo A-I, A-II, B, C-II, C-III and E were assayed by single radial immunodiffusion method. Plasma apolipoproteins decreased significantly during PE. Total amounts of apolipoproteins removed from two patients during each PE were as follows: apo B (case 1: case 2, 1, 300mg: 1, 540mg)>apo A-I (910mg: 546mg)>apo A-II (238mg: 164mg)>apo C-III (89mg: 104mg)>apo E (66mg: 70mg)>apo C-II (53mg: 70mg). Efficiency of PE in removing apolipoproteins did not change in the course of a year. After starting PE, angina pectoris was relieved.

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A young woman with homozygous familial hypercholesterolemia was treated with plasma exchange for three years and five months. The results were as follows:
1) Serum cholesterol level reduced and xanthomas improved. The patient was relieved from angina and syncopal attack after the treatment.
2) In the coronary angiogram, no progression of coronary atherosclerotic lesions were seen.
3) Left ventricular-aortic peak systolic gradients were observed to increase after three years of plasma exchange.
From these data, though plasma exchange appeared to be effective in improvement of the patient's clinical manifestations, reduction of serum cholesterol level appeared to be not enough yet. Thus further investigation of normalization of serum cholesterol level will be required. Some factors other than visible coronary lesions and aortic lesions may induce her angina.

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Atherosclerosis is produced by combination of various factors, among which high blood pressure and hypercholesterolemia are important accerelating factors contributing to atherosclerotic development through affecting aortic walls. The aorta has 3-layer structure consisting of the intima, the media and the adventitia. It is considered that each layer is differently influenced by these factors. Rabbits of 2.5-3.0kg were used as experimental animals. High blood pressure rabbits were bred for 7 months following the operation in which the renal artery was narrowed, and hypercholesterolemic rabbits were produced by 1% cholesterol feed for 12 weeks. Each aorta of the treated rabbits was prepared by perfusion fixation and was observed the cross section and the luminal surface by light microscopy and scanning electron microscopy to determine which layer these factors affected. Under anesthesia, the pressure of high blood pressure rabbits ranged 135/100mmHg and the mean pressure was 112mmHg which was 40mmHg (56%) higher than that of normal rabbits with pressure of 85/65mmHg and the mean pressure of 72mmHg. The mean level of serum cholesterol was 1, 376±396mg/dl 12 weeks after 1% cholesterol feed administration. This was much higher than that of normal rabbits with 43±21mg/dl. Light microscopy observation revealed that high blood pressure rabbits showed the thickening of the media by 15% and fragmentation of medial elastic fibers and rabbits with hypercholesterolemia showed remarkable thickening of the intima by cholesterol depositions and fibrosis. By scanning electron microscopic observation, endothelial cells of the aorta of high blood pressure rabbits were found to be long fusiform and their alignment was parallel to the long axis of the aorta. No remarkable changes were found as compared with normal endothelial cells. In luminal surface of the rabbits aorta with hypercholesterolemia, the frequent occurrence of atheroma and proliferation of microvilli on endothelial cells were found.
We had conclusions as follows. High blood pressure chiefly affects in the media and hypercholesterolemia mainly in the intima.

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In this paper, results of the one year follow-up on the effects of elastase on peripheral hemodynamics, platelet aggregation and other blood parameters in patients with arteriosclerosis are reported. Blood flow (BF) and maximum venous outflow (MVO) of the forearm and calf were measured by venous occlusion plethysmography using strain gauge to investigate peripheral hemodynamics in 10 patients (mean age 65.7 years) before treatment with oral administration of 10, 800 units of elastase per day, at 3, 6, and 12 months during treatment. Platelet aggregation, plasma β-thromboglobulin, plasma lipids, plasma euglobulin lysis time were also measured. Significant increase in BF of the bilateral forearm and calf was observed at 12 months following the treatment and MVO of the forearm and calf was also increased. Circulating platelet aggregates (ex vivo platelet aggregation) and plasma triglycerides decreased at 12 months following elastase treatment.
These results show that elastase may have beneficial effects on peripheral hemodynamics in the treatment of patients with arteriosclerosis.

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Examination of the coronary arteries and aortic tissue in swine by electron microscopy has shown that upto 6 months of age, various degree of fibrocellular intimal thickening had occured in those animals on a non-atherogenic diet. A mechanical denudation of the endothelium resulted in marked intimal thickening of the aorta, indicating that the endothelium has the role of protecting against plasma infiltration into the arterial wall. Ultrastructural study of the ductus vasculature disclosed that endogenous lipid synthesis can be accentuated under hypoxic condition. Lipid-rich arterial lesions, which were characterized by the presence of degenerate cells with or without stainable lipid were produced by feeding them either vitamin D or culinary fats without significant amount of cholesterol. These data suggested that other angiotoxic factors as well as hypercholesterolemia could be responsible for the development of atherosclerosis.

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We evaluated the plasma levels of thromboxane B₂ (Tx B₂) and 6-keto PG F_1α in both healthy controls and diabetic subjects before and after forearm ischemia, and the effects of trapidil on prostaglandin metabolism of these subjects. Our observations were listed as follows.
(1) Before ischemia, plasma levels of Tx B₂ and 6-keto PG F_1α were 101.4±75.0pg/ml (Mean±SEM) and 115.1±14.6pg/ml in controls, and 181.4±161.4pg/ml and 65.2±9.0pg/ml in diabetics, respectively. In diabetics, plasma levels of 6-keto PG F_1α was significantly lower than in controls (p<0.01).
(2) After ischemia, plasma levels of Tx B₂ and 6-keto PG F_1α were 177.1±136.2pg/ml and 227.4±10.5pg/ml in diabetics, respectively. In diabetics, forearm ischemia did not induce the increase in plasma level of 6-keto PG F_1α significantly, and was significantly lower than those in controls (p<0.05).
(3) After trapidil treatment in diabetics, plasma levels of Tx B₂ did not change significantly. Plasma levels of 6-keto PG F_1α was 82.7±22.8pg/ml before ischemia, and 127.7±23.1pg/ml after ischemia. After ischemia, plasma levels of 6-keto PG F_1α was significantly higher than those before treatment (p<0.01).
The results indicate that the secretion of prostacyclin to forearm ischemia is decreased in diabetics. These abnormalities may play an important role in the pathogenesis and/or development of diabetic micro- and macro-angiopathy. Trapidil, known as coronary vasodilator, would be useful for its promoting effect of prostacyclin production, although further study would be needed to elucidate the detailed mechanisms.

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