We investigated serum lipids, lipoproteins and apolipoproteins in various arteriosclerotic diseases such as coronary artery sclerosis, cerebral artery sclerosis, aortic artery sclerosis and peripheral artery sclerosis, and compaired each other to clarify whether or not there were any organspecific abnormalities of lipoprotein metabolism among these diseases. In comparison to the values of age-, sex-, TG-, TC-matched myocardial infarction, there were significant lower levels of HDL-TG (Aneurysma, male-CVD), %HDL-TG (Aneurysms, male-CVD), %LDL-TC (ASO), TC/B (male-CVD) and %Apo A-I (male-CVD). Although it is necessary to take other effectors on lipoprotein metabolism into consideration, these results suggest that there are some organ-specific abnormalities in lipoprotein metabolism among various arteriosclerotic diseases.

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It would be important to study the characteristics and the action of “dentured” or “modified” LDL in atherogenesity. We investigated whether modified LDL was formed in normal human and what effect this LDL had on human arterial smooth muscle cells in culture.
Incubation of plasma prepared from normal human was performed at 37°C for 6 hours. Thrombin was added to both of incubated plasma and also non-incubated plasma obtained from each subject in order to remove fibrin. Lipoproteins (VLDL, IDL, LDL and HDL) were ultracentrifugally isolated from each serum.
LDL obtained from incubated plasma had faster mobility than that from non-incubated plasma on agarose-gel electrophoresis. Lipids-composition (TC, TG, PL and Ch-ester) was altered in LDL after incubation. These alterations of LDL might be induced by lipid transfer protein. In this way, LDL obtained from normal human was modified.
DNA synthesis of human arterial smooth muscle cells (SMC) increased in the culture with LDL addition. This action of LDL was dose-dependent manner. DNA synthesis increased in the culture with modified LDL more than that with native LDL.
These data indicated that LDL obtained from normal human was easily modified and modified LDL influenced DNA synthesis of cultured arterial SMC.

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β-lipoprotein plays an important role in atherosclerosis, which is the major cause of morbidity and mortality in diabetics. The rapid clearance of LDL from plasma is dependent on a receptor binding with apoprotein B, the major protein of LDL particle, which is present on cell membrane. It has been demonstrated that chemical modification of lysine groups on apolipoprotein B interfers with the ability of LDL to bind to the high affinity receptor. It has been demonstrated that glycosylation of LDL would block lysine groups and lead to inhibition of the ability of LDL to interact with the LDL receptor.
The purpose of this presentation is to review our knowledge of non-enzymatic glycosylaton of β-lipoprotein with particular reference to method of measurement, of glycosylated β-lipoprotein.
Glycosylated β-lipoprotein was measured by affinity column chromatography. Following results were obtained.
1. Elevated glycosylated β-lipoprotein has been found in diabetes mellitus (DM).
2. There were good correlations between β-lipoprotein and total cholesterol or GHb in DM.
3. The catabolic rate for the glycosylated β-lipoprotein was lower than that of non-glyco-sylated β-lipoprotein in vivo.
4. Acetyl salicylic acid or pyridoxal phosphate competitively inhibited glycosylation of β-lipo-protein.
5. Glycosylated β-lipoprotein injured vasucular endothelial cells in vivo.

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Erythrocyte-α-tocopherol (RBC-Toc) in hemodialysis (HD) patients with high aortic caltification index (ACT) showed significantly low levels as compared with HD patients with low ACT.
RBC-Toc in patients was negatively correlated with high density lipoprotein (HDL)-Toc in contrast with healthy subjects.
After oral administration of Toc, the transfer to RBC-Toc was poor; contrarily, HDL-Toc showed a high level and an enantiomorphism with RBC-Toc.
In the experimental systems in vitro, the transfer of Toc from healthy subjects' HDL to patients RBC was found most preminent in the lecithin: cholesterol acyltransferase (LCAT)-containing system.
These findings demonstrated that a main factor for the lowering of RBC-Toc level which might be related to atherosclerosis may be insufficient transfer from HDL mediated with the LCAT reaction in HD patients.

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Four pedigrees with hyperalphalipoproteinemia (HALP) have been found since 1982 in Iwate Prefecture and total 5 homozygotes and 16 heterozygotes were studied for their plasma lipoprotein and apoprotein constituents.
As in familial hypobetalipoproteinemia, all HALP subjects demonstrated the decreased level of plasma LDL-C, which seems to contribute primarily to the low incidence of atherosclerotic disorders in these pedigrees. Furthermore, in HALP heterozygotes, longevity might be accerelated by the moderate increase of plasma HDL concentration.
Gradient-gel electrophoretic study revealed massive apoprotein E-rich matured HDL accumulation in HALP, suggesting impaired transfer and redistribution of cholesteryl ester to other lipoproteins.

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Cholesterol in lipoprotein has been estimated by analyzing the ultracentrifuged (UC) or precipitated material of serum, and also by calculation following Friedewald's formula. Preparative ultracentrifugation, being a time-consuming procedure, is not always available for routine laboratory work. Some inaccuracies have been stated in calculation following Friedewald's formula in cases with hypertriglyceridemia.
Recently Assmann et al developed a new LDL-cholesterol (LDL-Ch) assay method precipitating LDL by polyvinyl sulfate (PVS).
This paper describes an investigation of LDL-Ch by PVS method and compares with other methods.
Serum specimens were collected from 62 adults comprised of 24 with the triglyceride (TG) level of 150mg/dl or below, 15 with 180 to 299mg/dl and 23 with 300 to 520mg/dl. Chylomicron was removed after an overnight refrigeration at 4°C. Polyacrylamide gel disc electrophoresis for the supernatant separated by addition of PVS to serum demonstrated no LDL band indicating the complete sedimentation of LDL.
LDL-Ch level was higher in PVS method than in UC. The intraassay coefficient of variation of LDL-Ch by PVS method was 1.3% (n=10). The values obtained by PVS method and calculation following Friedewald well correlated positively with that obtained by UC irrespective of TG level. The inaccuracy of calculation following Friedewald owing to TG might be eliminated by the removal of chylomicron containing much TG in our observation.
PVS and Friedewald methods are superior to the ultracentrifugation method in clinical observation of dyslipoproteinemia, both methods should be widely applied in clinical practice.

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A method of double antibody radioimmunoassay (RIA) for rat apolipoprotein A-I is described. The apo A-I was isolated from delipidated HDL by SDS-polyacrylamide gel electrophoresis. Apo A-I was iodinated by chloramine-T method. More than 80% of ¹²⁵I-apo A-I was precipitated by an excess of anti-apo A-I antibody, and 95% of bound ¹²⁵I-apo A-I was displaced by unlabeled apo A-I. Any of other rat lipoproteins and apolipoproteins did not react in this system. Rat sera displaced ¹²⁵I-apo A-I in parallel with unlabeled apo A-I. Heating of diluted sera for 3hr at 52°C prior to assay resulted in maximal increases in apo A-I immunoreactivity to levels comparable to those found in the delipidated specimens. Levels of apo A-I in the media of cultured rat hepatocytes were measured by this system. Concentration of apo A-I in culture medium increased almost linearly for periods up to 24hr. Amount of apo A-I accumulated for 24hr was 1.6μg/mg cell protein.

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Whether light scattering index of serum (S-LSI) reflect the concentration of serum lipids, apolipoproteins and lipoproteins or not has been studied.
Subjects whose serum triglyceride (TG) level was below 700mg/dl were fasted for 13 hours and blood samples were obtained.
Serum was isolated by centrifugation, separated, and diluted 100 times with physiological saline. Light scattering index of serum (S-LSI) was measured by nephelometer (Nephelotik DN2110, Kyoto Dai-ichi Kagaku Co. Ltd.), Serum lipids were measured by enzymatic methods. Serum apoprotein levels were determined by single radial immunodiffusion method. Kits of apo A-I, A-II, E, C-II and C-III were purchased from Dai-ichi Kagaku Co. Ltd., and a kit of apo B was purchased from Hechist Co. Ltd. Serum lipoproteins were separated by sequential ultracentrifugation according to Havel's method. Lipoprotein concentrations were determined by totaling triglyceride, cholesterol and phospholipid contents in each lipoprotein fractions.
S-LSI was found to significantly correlated with serum triglyceride (r=0.94, p<0.001) and with serum phospholipid (r=0.47, p<0.001).
No correlation was observed between S-LSI and serum cholesterol (Fig. 1). A clear correlation between S-LSI and apo C-II (r=0.61, p<0.001), apo C-III (r=0.52, p<0.001) and apo E (r=0.48, p<0.001) was observed. On the other hand, no correlation was found with S-LSI and apo A-I, apo A-II and apo B (Fig. 2). There was a significant correlation observed between S-LSI and VLDL (r=0.90, p<0.001). There was a weak relationship found between S-LSI and LDL (r=0.41, p<0.05) as well as between S-LSI and HDL₂ (r=0.48, p<0.01) and S-LSI and HDL₃ (r=0.41, p<0.05, Fig. 3).
It has been concluded that S-LSI reflects the concentrations of serum TG, apo C-II, apo C-III and VLDL.

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The correlation of the cholesterol translocation with LCAT activity was further examined by using our newly devised in vitro incubation procedure, which enabled the quantitative estimation of cholesterol translocation between α- and β- lipoprotein.
The extents of translocation of free cholesterol from β- to α-lipoproteins, FC (β to α), and the translocation of esterfied cholesterol from α- to β-lipoproteins, EC (α to β), were larger in the high LCAT groups than those in the low LCAT groups. However, paradoxically, the amount of FC in β-lipoprotein fraction before incubation (βLpFC b. i.) was found to be much larger in the high LCAT groups than in the low LCAT groups.
The ratios of FC/EC in β-lipoprotein before incubation were nearly the same in both the low and high LCAT groups, but after incubation the ratios were lower in the high LCAT groups.
The HDL-C level as well as the HDL₂/HDL₃ ratio was definitely lower in the high LCAT groups than in the low LCAT groups.
It seems that both α- and β-lipoproteins have apparently the similar affinity toward FC and EC, although the size and apoprotein composition of the two lipoproteins are quite differents. Also it seems that some unknown extravascular factors might participate in the regulation of FC/EC ratio in β-lipoprotein in vivo.

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The effects of 2-week hyperinsulinemia on the production of very low density lipoprotein (VLDL)-triglyceride (TG) and on VLDL particle size were examined in rats. Hyperinsulinemia was induced by a constant subcutaneous infusion of 6 U porcine insulin per day from an osmotic minipump. To avoid profound hypoglycemia, these rats received chow plus 10% sucrose in their drinking water. We, therefore, examined two control groups: one receiving chow plus the same amount of sucrose (sucrose control) and the other receiving chow only (chow control).
Insulin infusion produced an increase in TG secretion in face of a decrease in FFA, suggesting that TG secreted in hyperinsulinemic rats were of non-FFA origin. Insulin infusion also produced an increase in serum TG and no change in serum glucose. The former suggests that stimulation of TG removal by hyperinsulinemia was equal to, but not greater than stimulation of secretion. The latter finding makes it unlikely that VLDL changes were caused by an increase in counter regulatory hormones.
VLDL particle size was increased in the sucrose control. This indicates that sucrose feeding leads to the production of more TG-filled VLDL particles. Hyperinsulinemia was not accompanied by any further increase in particle size. Thus, the hyperinsulinemia-induced increase in VLDL-TG secretion was accompanied by an increase in VLDL particle production.

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Recently, abnormality of lipoprotein is given attention as one of the risk factors for atherosclerosis. The size of lipoprotein particles obtained from patients with hyperlipidemia, diabetes, or coronary heart disease, was measured by high performance liquid chromatography.
In patients with hyperlipidemia, serum total triglyceride showed a reverse correlation with the size of low density lipoprotein (LDL) particles (r=0.5245): the size of LDL particles became smaller as triglyceride level became higher. In diabetic patients small-very low density lipoprotein (VLDL), which was between VLDL and LDL, was detected, and frequency of small-VLDL in patients with adequate control of blood glucose, lipids, and body weight was equal to that in patients with inadequate control. Small-VLDL was not found in diabetic patients who were treated with insulin. High density lipoprotein particles had an inclination to bigger size in patients with diabetes or coronary heart disease.

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In order to elucidate the heterogeneity of low density lipoproteins (LDL, d: 1.019-1.063), we performed hydrodynamic study of LDL using analytical ultracentrifugal method. By the analysis of schlieren pattern, LDLs were divided into two groups, monodisperse and polydisperse LDLs, respectively. The prevalence of polydisperse LDL was significantly (p<0.001) higher in hypertriglyceridemic patients than in normotriglyceridemic subjects. Polydisperse LDLs had lower flotation rate (Sf) and lower ratio of LDL-lipids/protein than monodisperse LDLs. These results indicated that polydisperse LDL was smaller and denser than monodisperse LDL.
Type IIa hyperlipoproteinemia with diabetes mellitus had polydisperse LDL more frequently than that without diabetes. Intermediate density lipoprotein (IDL) and cholesterol-rich very low density lipoprotein (VLDL) increased in diabetics. It was suggested that appearance of polydisperse LDL was related to metabolic derangement of VLDL and IDL.
We suspected that there might be catabolic disorder of VLDL and IDL and cholesterol-rich VLDL might be formed by the way of esterified cholesterol transfer from LDL or HDL to retained VLDL in subjects with polydisperse LDL. Tri-glyceride from VLDL might be oppositely transferred to LDL or HDL and the particle size of polydisperse LDL might become small due to hydrolysis of LDL-triglyceride by lipoprotein lipase (LPL) when this activity would be normal.
In conclusion, the appearance of polydisperse LDL might indicate the presence of catabolic disorder of VLDL and IDL.

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The liver plays an important role in the catabolism of High Density Lipoprotein (HDL). It has been difficult to identify HDL₃ receptor because of HDL₃ containing apo E. The present study is to elucidate the characteristics of HDL₃ receptor by studying the binding of HDL₃ with rat liver plasma membrane.
In HDL₃ isolated by sequential ultracentrifugation, the protein moiety consists more than 90 of apo A-I and A-II, and 0.1% of apo E. In isolated perfused rat liver, rat liver uptook 4% of HDL₃ within the first pass and its ratio did not increase by the treatment of Ethynil-Estradiol.
HDL₃ bound to the rat liver plasma membrane in the fashion of time, temperature, and pH dependence. At 4°C, the specific binding of HDL₃ was equilibrated and saturated after 60 min. The Kd was 11.0μg/ml. The binding sites showed heterogeneity by Scatchard analysis and the high affinity binding sites was 1.15μg/mg·membrane protein. The specific binding was Calcium independent and competed with HDL₃, but not with LDL. This suggest that rat liver has HDL₃ receptor different from apo B and E receptor and also apo E receptor. The HDL₃ receptor binding assay may be useful to estimate the physiological and pathological circumstances.

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In order to re-evaluate the significance of routine examination of HDL-cholesterol, we analyzed HDL subfraction-compositions by gradient-gel electrophoresis together with plasma concentrations of lipids and apolipoproteins in 65 diabetic patients (44 insulin-treated patients and 21 sulfonylurea-treated patients) without hyperlipoproteinemia. The lipoprotein patterns were found to be more atherogenic in the poorly-controlled patients than in the well-controlled patients either under insulin treatment or under sulfonylurea treatment. HDL-cholesterol increased significantly especially in the well-controlled insulin group. The analysis of HDL subfractions by gradient-gel electrophoresis revealed that the large, matured HDL particles (HDL_2b) were increased significantly in the insulin group with good glycemic control.
Although the direct evidence is still lacking, these matured HDL particles may reflect the antiatherogenecity in vivo.

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The changes of serum HDL subfraction and apolipoprotein were investigated in the subjects of fatty liver associated with abnormal liver function tests. Significant high levels of serum triglyceride, apolipoprotein C-II, and C-III were shown before treatment, whereas HDL-cholesterol and HDL₂/HDL₃ ratio were decreased. The calory restriction and administration of Elaszym (6 tab/day) have resulted in the amelioration of the parenchymal liver dysfunction, and concomitant recovery of serum lipid, lipoprotein, and apolipoprotein profile. These results suggested that the dyslipoproteinemia in fatty liver was similar to that observed in the original diseases such as obesity.

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Effect of long term regular aerobic training on the body weight, serum lipids and apolipoprotein were studied in 43 obese children (23 boys, 20 girls) initially aged 11 years. The training program consisted 20 minutes run with the heart rate of 140-150/min on two occasions per day for two years.
Obesity index (Broca's) decreased significantly (39 vs. 22%) in the first year. In both sexes, the HDL-C increased significantly in the first year and it tended to a little recess in the second year. Total cholesterol did not change, but apo A-I (n=19) increased significantly in the first year. There was significant reduction in triglyceride after two years in girls. In conclusion, the concomitant improvement in lipoprotein metabolism with significant weight reduction after regular aerobic exercise in obese children would be beneficial.

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Proline-rich protein (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 was correlated to serum total cholesterol and triglyceride, VLDL-cholesterol and VLDL-trigly-ceride and Apo B, C-II, C-III. These data suggested that PRP relates to the metabolism of TG-rich lipoproteins.

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Apo-lipoproteins constitute an important factor in arteriosclerosis. Dyerberg et al. demonstrated that Eicosapentaenoic acid (EPA) acts as an antiarteriosclerotic substance. However, the relationship between the amount of apo-lipoproteins and the content of fatty acids in serum remains unclear. Considering these circumstances, we attempted the analysis of serum fatty acids and the estimation of some apo-lipoproteins (Apo A-I, Apo A-II, Apo C-II and Apo E).
Blood samples were drawn from 45 subjects of healthy male and female. Fatty acids were analyzed by Gas chromatography and amounts of apolipoproteins were estimated by the method of SRID. No correlation was observed between fatty acids and either Apo A-I or Apo A-II. But there was a positive tendency between A-I/A-II ratio and the contents of EPA and DHA. A positive correlation was observed between Apo C-II and saturated fatty acids as well as monounsaturated fatty acids, but no correlation between Apo C-II and polyunsaturated fatty acids except for DHA. A positive correlation was also observed between Apo E and saturated fatty acids, but no correlation between Apo E and unsaturated fatty acids except for DHA.

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Plasma lipids, lipoprotein lipids and apolipoproteins were measured in 17 normolipidemic male patients with vibration disorder. All subjects had no other disease. Alcohol drinkers (n=9) were susteined abstinence during hospitalization for 6 weeks. There were no significant levels of these lipids and apolipoproteins between drinkers and non-drinkers (n=8) at the time of discharge.
The initial plasma triglycerides, apolipoprotein (apo) C-II, apo C-III, apo C-II/apo E and apo C-III/apo E levels were higher in drinkers than these in non-drinkers. The levels of apo C-II an apo C-III decreased significantly by abstinence. There were significant correlations between plasma triglycerides and apo C-II in non-drinkers at the time of admission and of discharge. This correlation did not exist in drinkers at the time of admission.
The values of LDL-cholesterol and apo B were not significant between in drinkers and in nondrinkers. These values were not changed during hospitalization. There were significant correlations between LDL-cholesterol and apo B in nondrinkers. This correlation did not exist in drinkers at the time of admission and there was significant correlation between apo B and plasma triglycerides in drinkers.
Initial HDL-phospholipids was higher in drinkers than in non-drinkers. Although, the values of HDL-cholesterol, apo A-I and apo A-II in drinkers were not significant in comparison with those in non-drinkers. These values decreased significantly in drinkers by abstinence.
These findings suggest that apo C-II and apo C-III are changed on these values in plasma and their distributions on lipoproteins by chronic alcohol intake. Apo B is changed its distribution on lipoproteins by alcohol consumption. Finally, HDL-cholesterol, apo A-I and apo A-II increase by alcohol drinking.

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The influence of various risk factors on the coronary atherosclerosis was studied on 274 male patients underwent coronary angiography. The severity of coronary atherosclerosis was positively correlated with the serum total cholesterol in the relatively young patients at the age of 54 years or less. Significant coronary atherosclerosis was more frequent in non-drinkers in this age group. On the other hand, the severity of coronary atherosclerosis was neither influenced by serum total cholesterol nor by the alcohol drinking in the patients at the age of 55 years or older. The significance of serum triglyceride, apo A-I, apo A-II, apo-B as well as the history of smoking and hypertension as risk factors of coronary atherosclerosis was not obvious in any age group in the present study.

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The purpose of this study is to clarify the relation between coronary stenosis and its background in patients with angina pectoris.
The subjects were 35 cases, aged 36-64 years without congenital heart disease, valvular disease, cardiomyopathy, myocarditis and myocardial infarction. As the items, age, coronary artery diameter, left ventricular mass, ejection fraction, aortic diameter, QRS voltage, ST-T changes, Master's two step test, atherogenic index, GTT, obesity index, cigarettes and blood pressure were taken. Each item was classified into two categories and then analyzed by quantification theory type III.
As the result of this study, the obvious correlations were observed in following three groups; 1) severe coronary stenosis, ST-T ischemic change and positive in Master's two step test. 2) hypertension and left ventricular hypertrophy. 3) increased atherogenic index and diabetes mellitus.

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The frequencies of apolipoprotein E phenotypes were determined in 208 subjects who underwent coronary angiography, using isoelectric focusing electrophoresis. The subjects were allocated into two groups: 152 patients with coronary atherosclerosis (group 1) and 56 controls with normal intact coronary artery (group 2). Observed frequencies were E 3/3=52.0% (n=79), E 3/2=19.7% (n=30), E 4/3=27.0% (n=41), E 4/4=0.7% (n=1) and E 4/2=0.7% (n=1) in group 1, while E 3/3=78.6% (n=44), E 3/2=7.1% (n=4) and E 4/3=14.3% (n=8) in group 2. The frequency of E 3/3 was significantly lower in group 1 than in group 2 (p<0.005), and the frequency of E 3/2 was significantly higher in group 1 than in group 2 (p<0.05). The frequency of E 2 heterozygotes (E 3/2, E 4/2) was significantly higher in group 1 than in group 2 (χ²=4.23, p<0.05).
VLDL cholesterol and VLDL triglyceride values were significantly elevated in E 2 heterozygotes (E 3/2, E 4/2) than in other phenotypes without E 2 (E 4/3, E 4/4, E 3/3) (p<0.01).
These results suggest that ξ2 allele may play an important role in genesis of coronary atherosclerosis.

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We have determined an aortic calcification index (ACT) calculated from to slices of abdominal CT scan according to the slightly modified method of Watanabe et al, and serum levels of lipids, apolipoproteins (apo) and α-tocopherol (TOC) in 9 patients with hyperlipidemia type II (HL), 11 patients with essential hypertension (H), 6 patients with ischemic heart disease (IHD), 5 patients with cerebral infarction (CI), 8 patients with diabetes mellitus (DM) and in 16 age-matched healthy controls (C). The mean age of all subjects was ranged from 60 to 70.
ACT was significantly higher in atherosclerosisrelated diseases (ARD) except H than in C.
Serum total cholesterol (TC) was significantly high in HL. HDL-C was significantly lower in ARD except HL than in C, while TC/HDL-C ratio was significantly higher in ARD than in C.
In HL and IHD, apo B levels showed a significant elevation when compared to those of C. On the other hand, apo B/A-I ratio elevated in DM as well as HL and IHD.
The changes similar to apo B/A-I ratio were obtained in TOC and malonyl dealdehyde (MDA) levels; an elevation of MDA and a reduction of HDL/(serum-HDL=non HDL) ·TOC ratio in HL, IHD and DM.
A significant correlation of ACT to TC/HDL-C, apo B/A-I and HDL/non HDL·TOC ratios was noted in all subjects. However, there was a significant relationship between ACT and these parameters in only HL among ARD.
The findings in the present study indicate that serum lipid abnormalities including lipid peroxidation may play an important role in The development of atherosclerosis in patients with hypercholesterolemia.

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Plasmalogen is a specific form of glycerophospholipid which is characterized by having long fatty aldehyde in α-position and high proportions of polyunsaturated fatty acids in β-position of glycerophosphate. It is suspected to have highly biological activity, but the function of plasmalogen in lipid metabolism is still unknown.
To elucidate the role of plasmalogen in progression of atherosclerosis, individual serum phospholipids including plasmalogen separated by two dimensional thin layer chromatography were determined in 43 control subjects and 48 patients with ischemic heart disease confirmed by coronary angiography. Furthermore, we analyzed β-chain fatty acid compositions of lecithin, cephalin, cholineplasmalogen and ethanolamineplasmalogen by gas chromatography.
Serum ethanolamine plasmalogen was significantly lower in the patients with ischemic heart disease (2.7mg/dl) than in the controls (4.8mg/dl). However, there was no marked difference in other serum phospholipids including cholineplasmalogen between the two groups. In the composition of fatty acids, ethanolamine plasmalogen contained considerably higher amount of polyunsaturated fatty acids, especially ω-3 group (linolenate, eicosapentanoate and docosahexaenoate), than other glycerophospholipids.
Polyunsaturated fatty acids of ω-3 group have strong suppressive effects on serum cholesterol and triglyceride, and preventive effects on thrombosis. A decline in the percentages of polyunsaturated fatty acids, especially ω-3 group in whole serum phospholipids, is caused mainly by the decrease of serum ethanolamine plasmalogen.
These results suggested that the changes in serum ethanolamine plasmalogen is related to the pathogenesis of coronary atherosclerosis.

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We investigated the effects of plasma triglyceride on the compositions of lipoproteins in 124 male patients with ischemic heart disease (IHD group) and 112 male patients without ischemic heart disease (non IHD group). We found large changes in the core portion of lipoproteins with increasing triglyceridemia. In both groups, the values of log TG has significant positive correlation with that of HDL-TG and LDL-TG and also a negative correlation with that of HDL-TC. In HDL of both groups, the amount of increased TG is equal to that of decreased TC, indicating that these changes of TG and TC are complementary each other. However, the compositions of HDL is 1.3 times more affected by TG in IHD group than non IHD group. These results seem to be useful to consider the atherogenecity of TG.

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To investigate the pathogenesis of vessel accidents such as myocardial infarction or angina pectoris, the following were studied,
a. The estimation of platelet aggregabilities in 36 IHDs and 24 healthy persons.
b. Periodical changes in platelet counts in 5 cases of acute myocardial infarction.
c. The changes of platelet aggregabilities with oxygen inhalation in 5 cases who required oxygen inhalation.
d. The comparison of platelet aggregabilities between arterial blood and venous blood in 5 cases with sclerotic disease.
e. The effect of CoQ₁₀ on platelet aggregabilities in 10 patients with sclerotic disease or hypertension.
1) The platelet aggregabilities were higher in IHDs than in healthy persons.
2) The platelet counts decreased immediately after myocardial accident and thereafter increased with recovery of GOT values day by day.
3) Oxygen inhalation made platelet aggregabilities show a lower trend.
4) The platelet aggregabilities in arterial blood showed a low trend compared with venous blood.
5) The platelet aggregabilities after CoQ₁₀ administration showed a high trend compared with those before CoQ₁₀ administration.
Most of the IHDs have sclerosis of the coronary artery and this will induce an ischemic state due to an insufficient supply of oxygen. The ischemic state might make platelet aggregabilities higher and will make the development of myocardial infarction easier. Furthermore, it might make the IHD more advanced in vessel injury or accident.
Therefore, oxygen inhalation is useful as a treatment for patients with myocardial infarction and also the management of sclerosis is very important to prevent the development of an ischemic state.

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This study was carried out to determine the changes in blood coagulation, fibrinolysis and platelet function in 81 patients with acute myocardial infarction from 1st to 30th day.
Levels of plasma fibrinogen markedly increased and reached peak levels on 7th day after myocardial infarction and remained elevated until 30 days. Changes in plasma levels of α1-antitrypsin and C₁-inactivator were similar to the changes of plasma fibrinogen.
Platelet count decreased during the first 7 days and gradually returned to the normal levels. Levels of β-TG and platelet factor 4, platelet-specific proteins, increased and reached peak levels on 3rd day after myocardial infarction and remained elevated for at least 2 weeks.
Levels of plasma antithrombin III decreased from 1st to 5th day and returned to the normal levels by two weeks after myocardial infarction. There were no significant changes in plasma α2-macroglobulin.
In fibrinolytic systems, levels of plasma plasminogen showed slight decrease for 2 to 3 days, but antiplasmin activities and levels of plasma α2-plasmin inhibitor increased and reached peak levels on 5th day after myocardial infarction and remained elevated during two weeks.
In acute period of myocardial infarction, increased antifibrinolytic activity was found accompanied with activation of blood coagulation and platelet. These changes returned to the almost normal levels within a month after myocardial infarction.

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The measurement of enzyme activity, such as creatine phosphokinase and aldolase, is not always specific in acute cerebral vascular disease. Therefore a convenient and useful enzymatic diagnosis is requested. First we measured serum adenylate kinase activity in healthy adults and patients with acute cerebral infarction by the decrease of NADH through the production of ADP. Adenylate kinase activity is highest in skeletal muscles but also exists in the brain. In our experiment the activity increased in the early days following acute cerebral infarction and then decreased gradually. We reported these results at the Annual Meeting of the 16th Japan Atherosclerosis Society.
In this report we studied the electrophoresis of adenylate kinase by using CK isoenzyme kits and had differential diagnosis between acute cerebral infarction and polymyositis through the pattern of adenylate kinase isoenzyme, namely, the rate of AK 1 increased in acute cerebral infarction and the rate of AK 2 increased in acute stage of polymyositis. We also studied adenylate kinase isoenzyme in rabbits with tournique shock and with experimental cerebral infarction. The results obtained were the same as those of human findings.
In conclusion it was observed that the measurement of serum adenylate kinase and the detection of AK isoenzyme are useful in the diagnosis of acute cerebral vascular disease.

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A total of 10 relatives with familial hypobetalipoproteinemia (FHBLP) was investigated for plasma lipoproteins, apolipoproteins and bile acid fractions in order to analyze the mechanism of this dyslipoproteinemia. The marked decreases in TC, TG, HDL-C, LDL-C and apolipoproteins A-I, A-II, B, C-II, C-III were confirmed in all relatives with FHBLP. The lipoproteins (LDL and HDL) were lipid-poor in the FHBLP subjects, showing the significant decreases both in LDL-C/apolipoprotein B and in HDL-C/apolipoprotein A-I. These results indicate the reduction of total cholesterol poor size rather than the reduction of individual apolipoproteins in FHBLP. We, therefore, analyzed plasma bile acids to get further informations on the body cholesterol metabolism. There was a significant decrease in glycine-conjugated chenodeoxycholic acid in the FHBLP subjects, thus suggesting that the reduction of cholesterol is not attributed to an accelerated cholesterol catabolism to bile acids but to a decreased rate of cholesterol synthesis.

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It is well known that the incidence of cholesterol gallstone is high in patients with type IV hyperlipoproteinemia (hypertriglyceridemia).
In the previous study, we demonstrated that the oncentration of serum squalene which represented the degree of cholesterol synthesis was increased in patients with cholesterol gallstone.
Then, the concentration of serum squalene was determined in several types of hyperlipoproteinemia without gallstone.
The result was as follows:
1) The serum squalene was significantly high in patients with type IV hyperlipoproteinemia and serum squalene levels correlated with serum triglycerides levels.
2) The ratio of squalene to triglyceride was significantly higher in patients with type IV than type IIa hyperlipoproteinemia.
3) The lithogenic index was significantly increased, and the ratio of cholic acid to chenodeoxycholic acid tended to increase in patients with type IV hyperlipoproteinemia.
These results may indicate that cholesterol synthesis is increased as well as triglyceride synthesis in patients with type IV hyperlipoproteinemia.
From above results, we conclude that type IV hyperlipoproteinemia is a preparatory state to form cholesterol gallstone in lipid metabolism.

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Elastase was administered to 28 patients with arteriosclerosis (cerebral infarction and effort angina) averaging 68.0±10.5 years in age at dose level of 5, 400 EL. U. for 6 months, and they were observed for effects of elastase on serum levels of lipids and platelet function during the treatment period. The following are the results obtained in this study.
(1) Serum levels of total cholesterol were significantly depressed (p<0.01) after 6 months of treatment.
(2) Serum levels of triglycerides were significantly depressed (p<0.05) as early as one month after onset of treatment.
(3) Serum levels of HDL-cholesterol tended to become elevated, and aterogenic index showed a significant improvement together with serum level of total cholesterol both at 3 months of treatment (p<0.05) and at 6 (p<0.01).
(4) Platelet function also improved, as reflected in a tendency of ADP, collagen and epinephrine aggregation in particular was significantly depressed (p<0.01) at 6 months of treatment.
(5) Plasma levels of β-thromboglobulin and platelet factor 4 tended to become depressed after onset of treatment.
(6) Plasma levels of thromboxane B₂ showed no change of significance, while plasma levels of 6-Keto-PGF_1α showed a tendency toward elevation after onset of treatment.
Those observations obtained in the present study suggest that elastase inhibits the process of platelet aggregation in the injured area of the blood vessel wall in modifying arteriosclerotic disease.

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Cultured mesothelial cells from bovine pericardium actively metabolize arachidonic acid, and the metabolites were identified as 6-keto prostaglandin (PG)F_1α, PGE₂ and monohydroxy acid in thin-layer and high-performance liquid chromatography. Although the monohydroxy acid was tentatively identified as either one of 5-, 8- or 11- hydroxyeicosatetraenoic acid, the isomeric form of the compound was not clearly determined. Quantitative measurement of 6-keto PGF_1α production by the cells in response to the stimulation with Ca ionophore A23187 or exogenous arachidonic acid disclosed the production of prostacyclin almost comparable to that by vascular endothelial cells. Cultured mesothelial cells produced a substantial amount of 6-keto PGF_1α in response to thrombin, histamine and bradykinin, as well. Receptor subtypes responsible for the actions of histamine and bradykinin were identified as H₁-and B₂-receptors, respectively, which are the same receptor subtypes involved in the stimulation of endothelial 6-keto PGF_1α production by these compounds.
Mesothelial cells virtually account for the arachidonate metabolism in the pericardium and the eicosanoids generated by the pericardium, with the access to coronary arteries and myocardium on the epicardial surface, may play an important role in the regulation of cardiac function.

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Recently the involvement of PGI₂ or Ca⁺⁺ has been discussed in reference to the development of atherosclerosis.
We, therefore, investigated the relationship between the intra- and extra-cellular Ca⁺⁺ and PGI₂ generation using cultured human vascular endthelial cells. Endothelial cells were isolated from human umbilical cord and cultured by the modified method of Jaffe et al. 6-keto PGF_1α content in the supernatant over the monolayer cells was used as the parameter of PGI₂ generation. The net influx of Ca⁺⁺ was calculated by counting the radioactivity of the incorporated Ca⁴⁵ (5μCi/ml) in the endothelial cells.
The obtained results are as follows: 1) Calcium ionophore A23187 (10_-6, 10_-5M) enhanced PGI₂ generation in a dose dependent manner. 2) The enhanced PGI₂ generation by A23187 was abolished in the Ca⁺⁺ free medium. 3) Intracellular Ca⁺⁺ immobilizer TMB-8 (10_-3M) abolished PGI₂ generation induced by A23187. 4) The net influx of Ca⁴⁵ increased parallel with the PGI₂ generation. 5) A23187 enhanced the net influx of Ca⁴⁵, 1.7 fold.
These results suggest that the enhancement of PGI₂ generation is originated from the increased cytosolic free Ca⁺⁺ by an influx of extracellular Ca⁺⁺ or a release of Ca⁺⁺ from the storage site. And it is concluded that suspected Ca⁺⁺ influx into vascular endothelial cells during development of atherosclerosis could enhance PGI₂ generation as one of the protective factors for atherosclerosis.

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We investigated the effect of thyroid hormone and methimazole administration in vivo on PGI₂ production in rats. Male Wistar rats (weighing about 250g) were treated with T₄ (200μg/100g body wt. ip every 24 h for either 3, 7 or 14 days e. g. groups 1, 2 and 3, respectively) or methimazole (0.01% in drinking water for 14 days, e. g. groups 7). For controls, rats were given corresponding amounts of saline ip every 24 h for 3, 7 and 14 days, e. g. groups 4, 5 and 6, respectively. Serum T₃ and T₄ levels were determined by RIA. Plasma PGI₂ levels, PGI₂ release by aortic rings incubated in vitro, were measured as 6-keto-PGF_1α by RIA. Serum T₄ levels in hyperthyroid rats (12.4±0.9, 8.3±0.9 and 9.2±1.2μg/dl for groups 1, 2 and 3, respectively) were significantly higher than those in control rats (4.5±0.3, 4.2±0.2 and 4.9±0.5μg/dl for groups 4, 5 and 6, respectively). Methimazole-treated group showed a significantly decreased serum T₄ level (0.9±0.1μg/dl). Serum T₃ levels in all T₄-treated groups were also significantly higher and that in methimazol-treated group was significantly lower than those in controls. Plasma PGI₂ levels in hyperthyroid rats (129.8±14.6, 137.5±17.3, 114.6±14.9pg/ml for groups 1, 2 and 3, respectively) were significantly higher than those in control rats (65.9±11.2, 53.3±10.2, and 58.2± 6.8pg/ml for groups 4, 5 and 6, respectively). However, plasma PGI₂ levels in group 7 was not different from that in control despite their decreased serum thyroid hormone levels. PGI₂ release by aortic rings in hyperthyroid rats (30.4±2.0, 34.2±2.0ng/mg aortic ring/15 min for groups 2, 3, respectively) was significantly higher than that in control rats (18.0±2.2, 20.4± 1.2 for groups 5, 6, respectively). In contrast, methimazole-treated rats showed a significant decrease in PGI₂ production by aortic rings (14.8±0.7, 20.4±1.2 for groups 7 and 6, respectively). There were no significant changes in phospholipid contents, fatty acid compositions of phospholipids, and phospholipase A₂ activity between controls and experimental rat aorta. These results suggest the stimulatory effect of thyroid hormone on PGI₂ production in vivo, although the mechanism of thyroid hormone action remains to be elucidated further.

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Association of lecithin: cholesterol acyltransferase (LCAT) with high density lipoproteins (HDL) was investigated using HDL-Sepharose chromatography and Sephadex G-200 gel chromatography. LCAT associated to HDL-Sepharose was dissociated by the reduction of ionic strength in the elution buffer. When fresh human plasma was gel-filtered through Sephadex G-200 in the absence of NaCl, the peak of LCAT activities was separated from that of HDL. The peak of LCAT shifted to that of HDL in the buffer containing 0.14 M NaCl. The incubation study of fresh plasma at 37°C demonstrated no enzyme reaction proceeded in the absence of NaCl. From these findings we conclude that a certain amount of ionic strength is indispensable to the association of LCAT to HDL and the LCAT reaction on HDL.

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