My studies were begun 25-26 years ago, which were reconfirement studies for Rinehart and Greenberg's experiments regarding to pyridoxine deficient monkeys. Since that time, I continued the studies on atherogenesis in pyridoxine deficient monkeys and regression of atherosclerosis in these monkeys. Many experiments have been done for many years, but the results which I got were very little.
However, it is certaine that there is slow progress in my studies. I think that some of my studies of the relationships between atherogenesis and homocysteinuria, between homocysteine and platelet, and between homocysteine and endothelial cells, have given the benefit for researches in atherogenesis. I remember a proverb that new finding is born from new technique. A part of progresses in my research, also, was born step by step from new technique which I created, but other parts of them were not born from myself. I will continue the research for the atherogenesis from now, also, with many mebers in JAS.

View full abstract

To clarify the metabolism of polyunsaturated fatty acids such as 5, 8, 11, 14-20: 4 (AA) and 5, 8, 11, 14, 17-20: 5 (EPA) acyl-CoA synthetase for these fatty acids and the incorporation of these fatty acids into complex lipids and CO₂ were investigated in the aorta of rats.
The activity of acyl-CoA synthetase was 35.9 for AA and 63.0 for EPA (nmoles/mg prot/10 min). The apparent Km values were 45 μM for AA and 56 μM for EPA. Inhibition of eicosapentaenoyl-CoA synthetase by AA was stronger than that of arachidonyl-CoA synthetase by EPA. AA and EPA were mostly incorporated into phospholipids. Compared with palmitic acid these fatty adids were less incorporated into C0₂ and cholesterol ester and more incorporated into triglyceride. Moreover these fatty acids were more incorporated into phosphatidyl (serine+inositol) and phosphatidyl ethanolamine. Between AA and EPA the incorporation pattern was almost the same. From the above results physiological role of these polyunsaturated fatty acids and the interference of AA metabolism by EPA were discussed.

View full abstract

Endothelial cells on the organization of thrombus are not only covered on the surface of thrombus, but also they are entered into thrombus from its base, in addition to smooth muscle cells, and then thrombus is organized.
Their organization are quite different by kinds of artery, nature of aortic wall and differences in composition of thrombus (fibrin, platelets etc).
In experimental thrombus that was formed by mechanical injury, smooth muscle cells are covered on the surface of thrombus. This effect was thought as temporary phenomenon till neiboured endothelial cells are covered.
In the relation between cultured endothelial cells and blood coagulation, some endothelial cells invaded into coagulation showed intracytoplasmic lumen at 14th days.
It was thought that this intracytoplasmic lumens reveal early phase of neolumen.

View full abstract

It has been known that exfoliation of endothelial cell is a factor of atherogenesis. Already, we reported that we observed the circulating exfoliated endthelial cells in man with Giemasa staining in accordance with the method of Hladovec, further with Ruthenium Red staining and direct immunofluorescent staining using anti-human factor VIII serum.
In this study, we examined these cells in man with direct immunofluorescent staining using anti-human α-2 macrogloburin serum, and loaded the rabbits with 1-methionine, d, 1-homocysteine, allylamine, serum with high β-lipoprotein, angiotensin II and fat emulsion, and loaded man with fat emulsion too.
The subjects were 72 healthy persons, 23 hemodialysis patients and the male rabbits which were 3-4 kg of body weight.
Result obteined were as follows;
1) With Giemsa staining these cells were shown, as a rule, polygonal shape, often with folded or rolled sugesting a marked flatness. The membrane of the cell was stanined with Ruthenium Red. And by the florescent staining, we could observe the intense fluorescence in the cell with anti-human factor VIII and anit-human α-2 macroglobulin serum.
2) When blood is taken with a syringe, endothelial cells may be detached and taken together. To prevend it, blood was taken from arterial side tube of extracorporeal circulation in hemodialysis patient and through the catheter in a rabbit. These sample showed the presence of cells. The average of the cell numbers in healthy subjects was ca. 1.59cells/9μ1PRP, and the average in hemodialysis patients was ca. 1.29 cells/9μ1 PRP, showing no significant difference between healthy subjects and patients. And diameter of these cells was ca. 20-50μm.
3) In the experiment with rabbits, administration of 1-methionine, d, 1-homocysteine, allylamine, serum with high β-lipoprotein, angiotensin II and fat emulsion caused all increases in cell count. With man, drip infusion of fat emulsion caused increases in cell count too.
These results were confirmed that these cells were circulating exfoliated endothelial cells.

View full abstract

Hypertriglyceridemia has been recognized as one of the risk factors in the development of atherosclerosis. But the mechanism by which VLDL act as atherogenic agents is not clear. It has been suggested that VLDL catabolism differed considerably when normal and hyperlipidemic subjects were compared. So in the present study we examined the composition and the nature of VLDL subfractions from hypertriglyceridemic subjects and normal.
1. Human VLDL
a) 39 hypertriglyceridemic subjects and 20 normal were examined.
b) VLDL were subfractioned by heparin sepharose 4B affinity chromatography into heparin unbound fraction (VLDLa) and heparin bound fraction (VLDLb).
c) VLDLb fraction contained relatively more cholesterol and less triglyceride than VLDLa fraction.
d) Apoprotein analyses of VLDL subfractions were performed by SDS-polyacrylamide gel electrophoresis. Apo-E was rich in VLDLb but not in VLDLa.
e) Particle size distributions of VLDL subfractions were examined by electron microscopy. VLDLa and VLDLb fractions from normal contained particles between 350-800Å (575±92Å) and 250-675Å (465±93Å) in diameter respectively.
f) The percentage of VLDLb in the d<1.006 fraction was significantly higher in hypertriglyceridemic subjects than normal. (88±8.4%, 74±14%, p<0.001)
g) Positive correlations existed in the % of VLDLb vs. plasma TG and the % of VLDLb vs. VLDL-TG. (r=0.305 p<0.05, r=0.509 p< 0.001)
2. Rat VLDL
Experimental hypertriglyceridemia was prodused by the feeding of 10% fructose containing solution for 2-4 ws. VLDL subfractions were examined in 10 hypertriglyceridemic and 8 control rats.
a) The % of VLDLb was also significantly higher in hypertriglyceridemic rats than control.
b) Positive correlations between the % of VLDLb vs. plasma TG and the % of VLDL vs. VLDL-TG were also observed.
It was suggested that VLDLb, which were smaller in size, depleted in triglyceride, and relatively rich in cholesterol and apo-E, might contribute to the development of atherosclerosis.

View full abstract

Elevated plasma cholesterol has been shown to be an independent risk factor for coronary heart disease. One of the consistent features of cholesterol-induced hypercholesterolemia in several animal species is the occurrence of β-VLDL in the d<1.006g/ml fraction. It has been shown that macrophage of mouse peritonium has a specific receptor for β-VLDL which does not bind LDL nor HDL. Cholesterolester laden macrophage might be a precursor of foam cell in athersclerotic lesion.
Liver is one of the most important organs which catabolize plasma lipoproteins. It has been shown that hepatocytes of several animal species have the receptors for lipoproteins; 1, a receptor which recognizes apolipoprotein (Apo) B or Apo E containing lipoproteins (B, E receptor), 2, a receptor which recognizes Apo E containing lipoproteins (E receptor) and 3. a receptor which recognizes HDL (HDL receptor). However, the role of liver parenchymal cell in the catabolism of β-VLDL has not been elucidated.
The purpose of the present study was to investigate the binding and degradation of rat β-VLDL by isolated rat hepatocytes. The β-VLDL was obtained from cholesterol and propylthiouracilfed rats. Isolated rat hepatocytes (5.0×10⁶ cells) were incubated with a fixed amount of ¹²⁵I-β-VLDL at 37°C for 60min in Krebs-Henseleit bicarbonate buffer, pH 7.4 with or without unlabelled β-VLDL. Binding was determined by radioactivity in washed cells. Proteolytic degradation was determined by trichloracetic acid and AgNO₃ soluble radioactivity in the incubated medium. Scatchard analysis of binding data for β-VLDL revealed nonlinearity of the binding which could be resolved into two components, suggesting the presence of two separate binding sites. The apparent dissociation constant (Kd) and maximum β-VLDL binding (Bmax) for the higher affinity binding site were 803ng protein/ml and 180ng protein/ 10⁶ cells, respectively. Kd and Bmax for the lower affinity binding site were 10, 390ng protein/ml and 1, 259ng protein/10⁶ cells, respectively. Proteolytic degradation was constant at least for 120min. Binding of β-VLDL was temperature dependent. In the Tris-HCl buffer containing 150mM NaCl, Kd of the higher and the lower affinity binding sites decreased 36% and 13%, respectively, as compared with those in the Tris-HCl buffer containing 25mM NaCl. Rat LDL and HDL₃ competed as well as native β-VLDL for the binding. Rat VLDL was as effective as 68% of native β-VLDL for the binding. Rat VLDL was as effective as 68% of native β-VLDL. Relative competivive potencies of cyclohexanedione treated β-VLDL was 47% of native β-VLDL. Human liporproteins were less effective than rat lipoproteins in competition for the binding. These data suggest that β-VLDL could be catabolized by hepatocytes through a specific receptor in rat.

View full abstract

The effects of various dextran sulfates (DS), which have different molecular numbers (DS-I∼V), on the hydrolysis of very low density lipoprotein-triglyceride (VLDL-TG) and on the stability of lipoprotein lipase (LPL) were studied. LPL was purified from bovine milk by affinity chromatography on heparin-sepharose 4B. Hydrolysis of VLDL-TG by LPL was increased by the addition of DS. As molecular number of DS becomes larger, the increase in Vmax values were observed. The apparent Km values for VLDL-TG were not changed. When LPL was incubated for 24hr at 4°C or for 2hr at 37°C, the enzyme activity decreased to 50% or 10%. But by the addition of DS, the activity was retained to the 90% or 50%, respectively. Large molecular numbers of DS (DS-III or V) stabilized LPL more than small molecular numbers (DS-I or II) did. Form these results, it was suggested that molecular number of DS might be important for the interaction of DS with LPL. When LPL was preincubated at 37°C for 1hr with or without DS-II, the hydrolysis rate of triolein emulsified with Triton X-100 was less drcreased in the presence of DS than in the absence of DS, but there was no difference between the rates of hydrolysis of VLDL-triolein in the presence or absence of DS. When VLDL-TG were treated with phospholipase A₂, the hydrolysis of VLDLTG by LPL was enhanced. DS did not increase the hydrolysis of VLDL-TG which were treated with phospholipase A₂ beforehand. These results suggested that the DS might act on the phospholipid in VLDL.

View full abstract

A normal control and a patient on maintenance hemodialysis, aged 30 and 35 years respectively, were investigated. Serum very low density lipoproteins (VLDL) were isolated by sequential ultracentrifugation and the resulting VLDL separated into two subclasses using Biogel A 15m column chromatography according to the method of Lusk et al (Biochim. Biophys. Acta, 710: 134, 1982). The VLDL subclasses were denoted as VLDL-I and VLDL-II depending upon the difference of the both elution steps in the gel filtration and metabolic aspect. VLDL-I which mainly originated from intestine was chromatographycally eluted faster than VLDL-II. VLDL apoproteins and apo B subunits were separated by 10 and 3.5% polyacrylamide electrophoresis in 1% sodium dodecyl sulfate, respectively. The results in this study were as follows.
1) In uremics, the VLDL-I/VLDL-II ratio was extremely lower than that of a normal control. The elution steps of VLDL-II in a patient delayed as compared with those of a normal control.
2) With respect to the chemical and apo-protein compositions of VLDL, VLDL-I and VLDL-II, no significant change was observed between two groups.
3) ApoB-48 was a main component in VLDL-I and there was no significant change in relation to the distribution of apoB-48 and apoB-100 in the VLDL subclasses between two subjects. The molecular weight of apoB-48 and apoB-100 was estimated about 240, 000 and 320, 000 on the bases of that of marker proteins, respectively.

View full abstract

The mechanisms of the triglyceride hydrolysis by hepatic triglyceride lipase (HTGL) were studied. Purified HTGL by affinity chromatography on heparin-Sepharose contained esterase activity, which hydrolized water soluble fatty acid ester, tributyrin as well as lipase activity which hydrolized triolein. The lipase activity was decreased by the addition by tributyrin, but esterase activity was enhanced by the addition of triolein emulsion, and dipalmitoylphosphatidylcholine (DPPC) vesicles. Kinetic analysis showed same Km values, and augmented Vmax values in the presence of DPPC vesicles. The enzyme was bound to the triolein emulsion even in the presence of tributyrin. These results indicated that HTGL has functionally two site; one is catalytic site, which hydrolizes ester bond, and the other is interface recognition site (IRS), and that the binding of the enzyme to lipid interface through ISR cause structural conformational change of the enzyme so as to increase the esterase activity, namely interfacial activation. Trypsin treatment caused a decrease in lipase activity with no change of esterase activity, and lost a process of interfacial activation. Binding capacity of the enzyme to DPPC vesicles was also decreased. These results indicated that trypsinsensitive protion was involved in IRS.

View full abstract

In order to investigate the relationship between plasma lipoprotein and coronary atherosclerosis, precise analysis of plasma lipoprotein concentration was made in 32 patients with angiographically confirmed coronary sclerosis (ASHD group: age 55.7±1). Control group was composed of agematched 22 patients with normal coronary angiogram. VLDL, LDL, HDL₂ and HDL₃ were fractionated with ultracentrifugation, and cholesterol (C), triglyceride, phospholipid, protein and apoprotein A-I, II in each fraction were determined. HDL-C concentration was lower in ASHD group than in control group. In the subfraction of HDL-C, HDL₂-C was significantly lower in ASHD group (17.9±1.4 vs 26.9±2.1mg/dl; p<0.001). In contrast, there was no difference in HDL₃-C. Thus, the decrease of HDL-C was caused by decrease of HDL₂-C. Phospholipid, protein and Apo A-I in HDL₂ were also decreased. Furthermore, the ratio of Apo A-I/protein in HDL₂ was significantly decreased in ASHD group than in control group (46.2±3.4 vs 62.2±4.2%). The composition of HDL₃ and LDL were the same in the two groups. In conclusion, the constitutional change of HDL₂ and possibly following change of the function might be related to the occurrence of coronary atherosclerosis as well as the quantitative decrease of HDL₂.

View full abstract

1) A new electrophoresis of lipoproteins was examined as a means of defining the hyperlipoproteinemia phenotypes. The serum lipoproteins of 119 cases with hyperlipoproteinemia whose serum total cholesterol (TC) concentration was greater than 250mg and/or whose triglyceride (TG) concentration exceeded 180mg per 100ml were determined by using a method of electrophoretic separation of lipoproteins on agarose and enzymatic staining of the each lipid component separately.
2) Based on the lipoprotein-lipids profile with the aid of various parameters for distinction, 119 patients were classified into WHO phenotypes of hyperlipoproteinemia. The percentages of phenotypes with those hyperlipoproteinemias were: type IIA, 31.1%; IIB, 33.6%; IV, 29.4%; and V, 5.9% respectively. But type I and III were not observed in this survey.
3) The characteristics of lipoprotein profiles of each phenotype were clearly identified, and they were: type IIA, high peak LDL-C and decrease of HDL-C fraction; IIB, high peak of LDL-C and VLDL-TG; IV, high peak of VLDL-TG; V, presence of chylomicrons and high VLDL-TG peak. With regards to mean HDL-C percent in TC and HDL-C concentration, both values were significantly low in type IIB and IV.
4) The serial observations of the lipoproteinlipids profiles were very useful to detect the progressive changes in lipoproteins which occured during the course of diseases, especially in the cases of secondary hyperlipoproteinemia.
In conclusion, a new lipoprotein-lipids profile by agarose electrophoresis-enzymatic staining do offer great help in classification of hyperlipoproteinemia and in therapeutic management.

View full abstract

Ultracentrifugal subfractionations of serum HDL, and the quantifications of apo A-I, apo A-II and cholesterol in each subfraction, were performed in 13 cases with cerebral infarction and 5 age-matched healthy controls. Apo A-I and A-II contents of HDL₃ were larger than those in HDL₂ both in patients and in controls. The average values of all three components in each subfaction in patients were significantly smaller than the values of corresponding components in controls. In addition, A-I/A-II ratio in HDL₂ was larger than that in HDL₃, and this difference was more pronounced in patients than in controls.
Apo A-I contents, but not apo A-II, in two subfractions correlated positively with HDL-cholesterol/total cholesterol ratio, reflecting the major role of apo A-I in HDL from the structural, as well as functional, points of view.
These results suggest that hypo-high-density lipoproteinemia in patients with cerbral infarction may be accompanied by the concomitant alteration in the subfractional composition of HDL.

View full abstract

A 50 year-old male was checked of distinctive elevation of HDL-cholesterol (HDL-C) in the routine examination and the intensive family study revealed the following characteristic findings.
1) The proband and one of his sisters had extreme high concentration of HDL-C; 181mg/dl and 163mg/dl, respectively. These 2 relative were supposed to be the homozygotes of familial hyperalphalipoproteinemia (Glueck et al. 1975). HDL-C values were found to be above the normal limit (Mean+1 SD of the age- and sex-matched controls) also in the other 7 of 11 first degree relatives of the proband.
2) All 5 children of the 2 cases with the homozygous disorder seem to be the heterozygotes since they showed the elevations of HDL-C (73-92mg/dl) all above the normal limit.
3) The present family analysis thus supports the autosomal dominat inheritance of familial hyperalphalipoproteinemia which Glueck et al. insisted in their report though failed to demonstrate the bimodality. Our report might be the first of homozygous familial hyperalphalipoproteinemia.
4) The deceased individuals of this pedigree showed an average life prolongation of 9.6 years as compared with the general population of the same district (Iwate Prefecture) at the corresponding period.

View full abstract

Effect of hypovitamin C on apoproteins in VLDL and HDL fraction was studied. Guinea pigs were fed with the commercial chow for the control and with scorbutogenic diet for the both groups were separated by SDS polyacrylamide gel electrophoresis and apo E isoform was identified by using isoelectric focussing method. In the hypovitamin C group, apo E in VLDL and HDL was increased as compared to the control (Fig. 1). Ratio of apo E to apo C in VLDL, ratio of apo E to apo A-I+apo C in HDL was calculated from the densitometric scans of the SDS polyacrylamide gels. Both of the ratio showed significant increase in the hypovitamin C group as compared to the control (Table 1). Isoelectric focussing patterns of apo VLDL were not remarkably changed in the control and the hypovitamin C group (Fig. 2). From these result, it was revealed that hypovitamin C had influence on the apoprotein metabolism. As one of the reason for the increase in apo E in VLDL, increase in transport of apo E from HDL to VLDL are supposed. In this transport of apo E, LCAT is required. Since the transport of apo E requires LACT, hypovitamin C may infleuence on this enzyme system. Another mechanism of increse in apo E is supposed that decrease in number of receptors to apo E and apo B in the liver is caused by hypovitamin C. Apo E rich HDL observed in this study may correspond to the HDLc reported by Mahley. It was considered that the competition between HDLc and LDL in the apo E, B receptor may contribute to stasis of LDL in hypovitamin C guinea pigs.

View full abstract

The pathological changes in the sinus of Valsalva was considered to be affected by coronary circulation and perfusion pressure, therefore the purpose of this study is to clarify the basic relation between the aging and the pathological changes in the sinus of Valsalva involved aortic valves and is to compare the cases of myocardial infarction with ones of non-myocardial infarction.
The subjects were 57 patients including 34 males and 23 females aged 22-74 years without congenital heart disease, valvular disease, myocardial infarction and cardiomyopathy and were 6 patients of myocardial infarction.
Results obtained were as follows:
1) Noduli Arantii was not clarified its relation with the aging but showed the tendency of increase in a small number in patients over sixties. Then the region of frequent occurrence was observed in posterior semilunar valve. Frenstration was thought to have no relation with the aging and the frequency was seen in left semilunar valve.
2) The existences of aortic commissural adhesions and fatty deposits both in aortic valves and in the sinus of Valsalva increased with the aging, but seemed to have no relation with each region and valve.
3) Fatty deposits of aortic valves were more frequent in the group of myocardial infarction than in the non-myocardial infarction.

View full abstract

It has been reported that there is a close relationship between aging and arteriosclerosis. In this experiment, we compared the lipid metabolism in 2 year-old rat with that of the arteriosclerotic rat which is fed on high-cholesterol and propylthiouracil diet and administrated vitamin D₂. The purpose is to clarify the role of aging in the formation of arteriosclerosis. The serum LDL-cholesterol, LDL-triglyceride and LDL-phospholipid were increased in aged rats compared with the young control rats. As for the lipid metabolism in arterial wall of aged rats, activities of acid cholesterol esterase (acid CEase), neutral CEase, neutral lipase, acyl CoA synthetase (Acyl CoA syn.), triglyceride synthesizing activity (TG syn.) and acyl CoA: cholesterol acyl transferase (ACAT) were increased. Choline phosphotransferase (CPT) activity was decreased. Acid lipase activity was not changed. In the arteriosclerotic rat arterial wall, activities of acid lipase, neutral lipase, Acyl CoA syn. and cholesterol easter synthesizing actity (CE syn.) were increased. Activities of acid CEase, neutral CEase and CPT were decreased. Activity of TG syn. was not changed. The common changes of these two conditions were increment in activities of neutral lipase, Acyl CoA syn. and CE syn. and decrease in CPT activity. The decrease of phospholipid content observed in aged rat's aorta might be due to the decrease of CPT activity.

View full abstract

Effects of aging on serum lipoproteins and subclasses of apolipoprotein C in VLDL were investigated in healthy male subujects from 0 to 8th decade.
Increase of serum lipid concentrations by aging, which reached the highest at 5th and 6th decade, was due to the elevation of serum LDL. VLDL and HDL did not show the age-related changes.
Percentage of free cholesterol in lipoproteins increased significantly in every lipoprotein fractions from the aged group at 5th and 6th decade when compared with that from the young group at 1st and 2nd decade. Apolipoprotein content in LDL from the aged group was lower than that from the young.
Apo C II/Apo C III ratio in VLDL increased parallel with the change of serum lipid concentrations by aging. Therefore, the activation ability of lipoprotein lipase may be not impaired with aging.

View full abstract

Controversy exists as to whether atherosclerotic lesions were reversible or not. These conflicting views chiefly derived from differences of animal species, experimental designs, or methods of evaluation. In the present study we attempted to quantitate sequential changes of sclerotic lesions with an aid of the image processing system.
Normotensive and hypertensive rabbits were placed on a 0.5% cholesterol diet for 16 weeks and observed up to 60 weeks. Prior to cholesterol feeding constriction of bilateral renal arteries were performed in the latter group and established hypertension with systolic pressure of 150mmHg or over. After we had measured surface involvement (SI) of atherosclerotic lesions by point counting method, a representative longitudinal section covering whole length of the aorta was obtained from each animal, and histometric quantitative analysis was carried out concerning foam cell infiltration, fibromuscular proliferation, and atheroma formation.
In normotensive rabbits sclerotic lesions had a predilection for the proximal portion of aorta, especially aortic arch and thoracic segment. Hypertensive rabbits exhibited more extensive and accentuated lesions not only in the thoracic but also in the abdominal portions of the aorta. Sequential reduction of SI was noted in normotensive rabbits especially after 40 weeks, but not in hypertensive ones.
After cessation of cholesterol feeding foam cell lesion of normotensive rabbits was gradually replaced by fibromuscular tissue. A greater degree of smooth muscle cell proliferation was a characteristic feature of hypertensive rabbits, even after 16 weeks. Formation of atheroma occurred almost invariably after 28 weeks both in normotensive and hypertensive animals. It was noted that hypertension accentuated the severity and extent of aortic atheroma.
Evidence of regression of non-atheromatous lesion was obtained in normotensive rabbits sacrified after 40 weeks and 60 weeks, while atheromatous lesion remained unchanged. Raising blood pressure resulted in no decrement of both atheromatous and non-atheromatous lesions in response to serum cholesterol reduction.
In conclusion, the present study indicated that regression in aortic atherosclerosis occurs in early lesions but seems difficult in advanced atheromatous ones. Hypertension remarkably accelerates both proliferation of fibromuscular elements and increment of advanced atheromatous lesions which are most probably concerned with aggravation and irreversibility of atherosclerotic process.

View full abstract

Male Wistar rats weighing 280g were subjected to the stress condition in which the rats were thrusted unceasingly and harassingly with a bamboo stick by the reseacher, for twenty minutes a day for a period of three and twelve months. The blood pressure reached a high mean value (191±3 S. E.) in twelve months. Mean organweight to body-weight ratios of heart, kidney and adrenal gland when compared to nonstressed controls were increased, and that of thymus was decreased. One of the animals subjected to the stress developed significant vascular pathology in the form of panarteritis like arteriopathy and simple fibrous intimal thickening, and others disclosed nothing of vascular changes. The analysis of relative thickness of media to radius in the branches of coronary arteries resulted in no change between subjected rats and controls in thickness of media, compared to that of spontaneously hypertensive reats (SHR) which disclosed medial hypertrophy.

View full abstract

Effects of various high fat cholesterol diets on plasma cholesterol levels and lipid deposition in the liver were examined in male stroke-prone SHR and stroke-resistant SHR. The diets contained basically 5% cholesterol, 2% bile acid and 20% of various lipids. The used lipids were suet, soybean oil, olive oil, palm oil (containing 10% safflower oil) or hydrogenated fish oil (melting point 30°C), respectively.
Total plasma cholesterol level was remarkably increased and HDL cholesterol levels was decreased in the rats after fed on suet diet, so that atherogenic index, LDL cholesterol/HDL cholesterol was extremely increased after fed on suet diet. Even though olive oil and soybean oil contained a lot of unsaturated fatty acids, the atherogenic indices in the rats fed on each diet were significantly higher than those fed on palm oil or hydrogenated fish oil diet. Also, suet oil and olive oil diet feeding accelerated fat deposition in the liver significantly more intensely than palm oil or hydrogenated fish oil feeding. Melting points of the deposited fat in the liver were significantly correlated with the liver weights on the degree of fatty metamorphosis of the liver.
These results suggest that the deposited lipids in the liver were markedly different in quality and quantity depending on the dietary fat constituents.

View full abstract

Human umbilical endothelial cells and smooth muscle cells in culture are done in a pressure chamber at 80mmHg, 120mmHg and 160mmHg respectively. The endothelial cells are very sensitive to the pressure, however smooth muscle cells are resistent against it and keep growing. The former changed their morphology minimal at 80mmHg, moderate 120mmHg, but so damaged at 160mmHg 24 hours after pressurization that cellular degeneration and necrosis begin.
Endothelial cells promptly react the arachidonic acid and convert it to prostacyclin. It reached maximum 15 minutes after administration. When pressurization at 80mmHg and 120mmHg, the function is depressed but at 160mmHg the synthesis of prostacyclin surpasses over the control of non pressure. This means the heavily damaged cells released a lot of converting enzyme to prostacyclin.
These phenomenon is correlated to the pathogenesis and progress of atherosclerosis in high blood pressure. It suspect that endothelial injury and the following platelet aggregation in high blood pressure induce the intimal thickning and atheroma formation and finally complelt the atherosclerosis.

View full abstract

The prospective study was performed in 638 patients with arteriosclerosis (344 male, 294 female) in order to analyze the risk factors in the development of myocardial and cerebral infarction. The mean observation period was 11.5 years.
Hypertension, hyperlipidemia, glucose intolerance, obesity, hyperuricemia and smoking were employed as risk factors for the analysis.
1. Myocardial infarction was observed in 67 patients (male 56, female 11) during the observation period and the incidence was 10.5%. The mean age at their attack was 64.7 years old.
In these patients, hyperlipidemia was found in 49, hypertension in 46, smoking in 43, hyperuricemia in 37, obesity in 30 and gluscose intolerance in 28 cases.
2. Cerebral infarction was observed in 76 patients (male 52, female 24) and the incidence was 11.9%. The mean age was 65.3 years old. In these patients, hyperlipidemia was found in 57, hypertension in 55, glucose intolerance in 41, obesity in 36, smoking in 35 and hyperuricemia in 20 cases.
3. Hyperlipidemia, hypertension and smoking were the three major risk factors associated with myocardial infarction. Almost 95.5% of patients with myocardial infarction were found to have one or more of these factors.
Hyperlipidemia, hypertension and glucose intolerance were the three major risk factors associated with cerebral infarction. One or more these factors were found in 97.5% of patients with cerebral infarction.
4. The serum cholesterol level in patients with myocardial infarction (237.5±39.6mg/dl) tend to be higher than in those with cerebral infarction 213.7±41.8mg/dl), while the serum triglyceride level in patients with myocardial infarction (137.2±43.8mg/dl) tend to be lower than in those with cerebral infarction (156.8±54.8mg/dl)
5. The mean level of HDL-cholesterol was 41.5mg/dl in patients with myocardial infarction and 44.4mg/dl in patients with cerebral infarction. Both of these HDL-cholesterol levels were shown to be significantly lower than in normal control subjects.

View full abstract

Plasma levels of lipids (cholesterol: T-C, triglyceride: TG, high-density lipoprotein cholesterol: HDL-C) and apolipoproteins (apolipoprotein A-I and A-II: Apo A-I, Apo A-II) were studied in 110 survivors of cerebral infarction (C. I., male: 77, female: 33) and 54 healthy controls (male: 39, female: 15). The levels of Apo A-I and Apo A-II have been measured by single radial immunodiffusion (SRID) method (Daiichi Kagaku Yakuhin).
Females had significantly higher HDL-C and Apo A-I levels than males in the control group, whereas no singificant differences in Apo A-II levels were found between both sexes.
The mean levels of Apo A-I and Apo A-II as well as of HDL-C for both sexes of the survivors of C. I. were significantly lower than those in the healthy controls. Apo A-I correlated strongly with Apo A-II in both groups. HDL-C correlated significantly with Apo A-II except for women in the healthy group. HDL-C correlated only weakly with Apo A-II in men in the healthy group, and no significant correlation was found for men in the C. I. group and for women in both groups. The ratio of Apo A-I/HDL-C was significantly higher in survivors of C. I. with high plasma level of TG than in those with normal plasma level of TG.

View full abstract

Conrad et al reported that the administration of allylamine to dog cause an injury of the arterial wall and the development of arteriosclerosis. Greenberg et al reported that pyridoxine deficiency in the Rhesus monky induces arteriosclerosis similar to that occuring naturally in man. Recently we found that allylamine itself aggregate platelet and pyridoxol phosphate inhibit allylamine induced platelet aggregation.
From these results it is suggested that platelet aggregation play important role in the arteriosclerosis caused by administration of allylamine.

View full abstract

Forty-nine outpatients with precordial pains were studied by the treadmill exercise test. Before, immediately after and 30 minutes after exercise, blood samples were obtained from antecubital veins, measuring plasma TXB₂, 6-keto PGF_1α, cyclic AMP and cyclic GMP levels by radioimmunoassay. The results of exercise tests were evaluated with the treadmill exercise score (TES) by Hollenberg et al, by which the patients were divided into two groups, TES (-) with ischemic findings in exercise and TES (+) with normal exercise. Changes of plasma prostanoids and cyclic nucleotides in each group were analyzed. There were no differences in TXB₂ levels between two groups before exercise. Immediately after exercise statistically significant difference of TXB₂ levels were present between two groups, resulting from the increased levels in TES (-) group and decreased in TES (+) group (p<0.01). Although 6-keto PGF_1α levels also showed no differences between two groups before exercise, 6-keto PGF_1α levels in TES (+) group were increased statistically significantly immediately after exercise. In consequence statistically significant differences (p<0.01) were observed between two groups and between the levels before exercise and immediately after exercise in TES (-) group. Similar changes were present in cyclic nucleotiedes, especially cAMP levels before exercise between two groups (p<0.05) and their differences increased more immediately after exercise (p<0.01). In ischemic heart disease, prostaglandins might play an important roles, especially the failure of PGI₂ production to counteract to the increase of TXA₂ by exercise may be an important phenomena to know the physiological conditions of ischemic heart disease.

View full abstract

For identification and characterization of the alpha and beta adrenoceptors, radioreceptor binding assays using a potent alpha adrenergic antagonist [³H]-WB4101 and a beta adrenergic antagonist, [³H]-dihydroalprenolol hydrochloride (DHA) were performed using cultured smooth muscle cells and endothelial cells from bovine aorta and which were harvested after six passages by the U'Prichard method modified by us.
Specific [³H]-WB4101 binding to cultured smooth muscle cell homogenates was confirmed be saturable, reversible and high affinity (Kd=0.28nM with a B max of 55.6fmol/mg of protein). Scatchard plots were linear suggesting a single population of binding site (α-receptor). Adrenergic agonists competed for specific [³H]-WB4101 binding in the order prazosin>phentolamine>>yohimbine> (±) -propranolol.
Thus, vascular smooth muscle cells seem to be equipped with alpha-adrenoceptors labelled selectively with [³H]-WB4101. However, these specific bindings with [³H]-WB4101 were not demonstrated in the cultured endothelial cells.
On the contrary, both cultured smooth muscle cells and endothelial cells revealed specific [³H]-DHA bindings characterized by saturable and reversible features. Scatchard analysis exhibited a linear plot in both smooth muscle cells and endothelial cells. Kd and B max were 0.33nM and 173.2fmoles/mg of protein in smooth muscle cells and 0.2nM and 26.9fmoles/mg of protein in endothelial cells.
The selectively binding receptors in the cultured endothelial and smooth muscle cells may relate to modulation of the vascular tone.

View full abstract

The pulmonary trunk was structurally similar to the elastic type artery of the ascending aorta, in which smooth muscle cells and fibroblast-like cells were the main cellular components.
The distal portion of the thoracic aorta was structurally identical to that of the mammalian species. The abdominal aorta, a muscular type artery, had more fibromuscular intimal thickening than the coronary artery both in degree and frequency.
The arterial smooth muscle cells in aged roosters displayed many degenerative changes, including pyknosis of the nucleus, cytoplasmic fragmentation, lipid vacuole and lipofuscin pigment.
Immature virus particles were observed in intimal smooth muscle cells, and many mature virus particles appeared in intercellular spaces. Some smooth muscle cells containing virus particles displayed pyknotic and cytolytic changes even in young chickens.

View full abstract

We studied serum lipoproteins and apolipoproteins in the patients with or without coronary artery disease (CAD) in order to clarify the relationship between abnormal apolipoprotein metabolism and incidence of CAD.
The subjects in this study were 49 males and 51 females who were outpatients of our clinic or inpatients of coronary care unit.
Apolipoprotein (apo) A-I and A-II were determined by means of single radial immunodiffusion (SRID) method kit (Daiichi Pure Chemicals Co. Tokyo).
The subjects were divided into two groups according to the levels of T-CH, hypercholesterolemic group (T-CH≥250mg/dl) and normocholesterolemic group (T-CH<250mg/dl)
We studied the corrleationship between serum HDL and apo A-I or apo A-II, and the difference of serum apo A-I and A-II levels between the patients with and without CAD.
The results were as follows:
1) There was positive correlationship between HDL-CH and apo A-I or A-II, especially among males. The relationsip between HDL-CH and apo A was statistically stronger in CAD positive group than negative group.
2) The levels of apo A-I and apo A-II were significantly lower in CAD positive group, especially in males.
3) There was no significant difference in the ratios of apo A/HDL-CH between the patients with CAD and without.
4) The ratios of apo A/LDL-CH were singificantly low in CAD positive group and the higher this ratio the higher incidence of CAD.

View full abstract