To examine the frequency distribution of Lp (a) lipoprotein levels in Japanese children, we measured the Lp (a) lipoprotein levels and other lipid levels of 178 school-age children (158 unrelated children) and 99 male adults living in the same district. The Lp (a) distribution was highly skewed and there was no significant difference between school-age children and male adults, with means and medians of Lp (a) lipoprotein levels at 15.8±17.2mg/dl (±SD) and 10.4mg/dl in children, and 18.6±19.6mg/dl and 12.0mg/dl in adults, respectively. Moreover, it was suggested that Lp (a) lipoprotein levels of Japanese children are not lower than those in Caucasian children. Positive correlations were observed between these Lp (a) lipoprotein levels and levels of serum cholesterol, LDL-cholesterol and apolipoprotein B in Japanese school-age children. No correlation, however, was observed between Lp (a) lipoprotein levels and corrected LDL-cholesterol levels. In addition, mean serum cholesterol levels were significantly higher in children with Lp (a) lipoprotein levels above 30mg/dl than in those with Lp (a) lipoprotein levels below 30mg/dl. These findings suggest that Lp (a) lipoprotein somewhat influences the cholesterol level in school-age children.

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We investigated the effects of β-blockers without partial agonistic activity on 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CR) activity in cultured human skin fibroblasts based on the β₁-selectivity. The β-blockers were used at concentrations equivalent to the plasma levels of β-blockers following clinical doses.
Propranolol is a non-selective β-blocker. Lpropranolol, an active form, significantly increased HMG-CR activity, while d-propranolol, an inactive form, failed to change HMG-CR activity. Metoprolol, a β₁-selective blocker, failed to change HMG-CR activity. On the contrary, betaxolol, which has a β₁-selectivity that is 2 to 5 times stronger than that of metoprolol, significantly decreased HMG-CR activity. The β-blockers did not affect the cell growth in the present study.
These results suggest that β-blockers affect HMG-CR activity through β-receptors and that β₁-selectivity is an important factor in determining the effect of β-blockers on HMG-CR activity.

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Adenylate cyclase in vascular endothelial cells (EC) has not been adequately defined. We investigated the effects of various agonists on adenylate cyclase activities in EC and compared those of smooth muscle cells (SMC) to assess the importance of these agonists in endothelial functions which employ cyclic AMP as a second messenger in signal transduction.
Cultured EC and SMC isolated from the same specimen of fetal bovine aorta was used to prepare a crude membrane fraction for an adenylate cyclase assay and for application of the adenine prelabeling method to determine cyclic AMP accumulation in intact cells.
Although the basal adenylate cyclase activities of EC and SMC did not differ significantly (18.9±0.8, 21.4±1.7pmol/mg protein/min, respectively), responses to some agents were quite different. The adenylate cyclase of the EC responded dramatically to catecholamines (both β₁ and β₂), and responded fairly well to calcitonin gene-related peptide (CGRP). However, it responded poorly to prostaglandins (PGE₁ and PGI₂) and glucagon.
In contrast, the adenylate cyclase of SMC was more sensitive to the prostaglandins and glucagon than that of EC. However, it responded less dramatically to catecholamines and was almost exclusively sensitive to β₁-agonists. F^-, GTP-γ-S and forskolin increased the adenylate cyclase activity of SMC much more than that of EC.
On the basis of these findings, it was concluded that responsiveness of EC and SMC adenylatecyclase to agonists including hormones, prostagrandins and peptides differed significantly. In EC, β agonists seemingly play an important role in cellular functions which are mediated by the increase of cAMP.

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Human plasma low density lipoproteins (LDL) consist of multiple subclasses differing in size, density and chemical composition. In 1986, Austin and Krauss identified that two distinct LDL subclass patterns (patterns A and B) use gradient-gel electrophoresis, with pattern B being characterized by a preponderance of small and dense LDL particles. Additionally, they reported that individuals with pattern B had a significantly higher risk of coronary heart disease. However, no investigation of the LDL subclass patterns was performed on patients with cerebral infarction. In this study, the LDL patterns of fifty patients with cerebral infarction and fifty healthy controls were determined through gradient-gel electrophoresis analysis.
The findings indicate that the mean particle diameters for LDL pattern A were 26.5±0.4nm (mean±SD) and that those for pattern B were 25.4±0.3nm. Pattern B was observed in twentysix percent of the patients with cerebral infarction (13 of 50 patients), but only in six percent of the healthy controls (3 of 50 subjects). In particular, pattern B was more frequent in patients under the age of 69 with cerebral infarction than in patients over the age of 70 (44% vs. 16%, respectively).
In subjects with pattern B in both the control and patient groups, the mean level of plasma total cholesterol (191±35mg/dl) did not significantly differ from the mean level in subjects with pattern A (187±37mg/dl). However, the mean level of plasma triglyceride (161±87mg/dl) was higher, and the mean level of HDL₂-C (9.8±5.3mg/dl) was lower in subjects with pattern B than in subjects with pattern A (101±37mg/dl, 18.2±9.2mg/dl, respectively). Moreover, in subjects with pattern B, the mean level of plasma apo B was higher, and the mean ratio of LDL-cholesterol/apo B (1.25±0.33) was lower than in subjects with pattern A (1.40±0.30, respectively). Similarly, in the pattern B patients with cerebral infarction, the mean triglyceride level was higher, while the mean HDL₂-C level and the mean LDL-C/apo B ratio were lower than in the pattern A patients.
Two family studies of subjects with pattern B have suggested that some LDL subclass pattern B subjects possess an autosomal dominant heredity trait.
We concluded that small, dense LDL (pattern B) associated with a relatively high triglyceride level and a low HDL₂-C level, is one of the risk factors for cerebral infarction, especially in younger old individuals.

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The ultrastructural changes and permeability of endothelial cells which are located in both lesionresistant and susceptible regions on the flow dividers at bifurcations of the brachiocephalic trunk and left subclavian artery were studied. Sixty-four and 22 male white adult rabbits were fed for up to 2 weeks with a cholesterol diet and a stock diet, respectively. For the permeability studies, horseradish peroxidase (HRP), ferritin and immunoglobulins against HRP produced autologously were used as tracers. Sudan IV stain revealed that the apex and leading edge of the flow dividers were spared from lipid deposition in the second week of the cholesterol diet. The deposition could be observed in a band-like fashion in regions 460μm downstream from the apex of both flow dividers. Apo E and B deposition was also immunohistochemically detected in the sudanophilic areas. Foam cells appeared successively following lipid deposition. Endothelial cells at the leading edge, lesion-resistant area, were elongated along the flow direction and had more microfilament bundles and fewer mitochondria in their cytoplasms, as well as thick basement membranes. In the shoulders, a lesion-prone area, they had more vacuoles, RER, Golgi apparatuses and mitochondria, but had fewer stress fibers in their cytoplasms. The permeability of endothelial cells to HRP and ferritin was enhanced in the shoulders of even normal rabbits. Permeability to immunoglobulins increased only in the shoulders of hyperlipidemic rabbits. The glycocalyx on the endothelium of normal rabbits was thicker at the leading edge than in the shoulders. Hyperlipemia decreased the thickness of glycocalyx at both the leading edge and in the shoulders, although this was more obvious in the shoulders.
In conclusion, lesion-prone areas in rabbits are located in areas exposed to low-shear stress just as in humans. These areas showed a higher permeability even in normal rabbits.

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We reported a 33-year-old man with hypolipidemia observed with Crow-Fukase syndrome. The subject suffered from hypolipidemia notwithstanding good nutritive conditions and a decreased thyroid function. The concentrations of serum total cholesterol and triglyceride were both 90mg/dl. The serum estrogen concentration was moderately increased. An electron microscopy of the liver specimen revealed degenerated hepatocytes. An increased estrogen concentration possibly coupled with decreased protein synthesis in the liver might have contributed in part to hypolipidemia in this patient. A review of cases with Crow-Fukase syndrome in the literature disclosed that 71% of all reported cases had hypolipidemia, which suggested that hypolipidemia may be more than mere coincidence in our patient. Although it has received little attention to date, hypolipidemia may be one of the principal clinical features of patients with Crow-Fukase syndrome. However, the mechanisms which cause hypolipidemia are still unknown. Further studies in the future wouldd prove useful.

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In many cases with hypertension, diabetes and hyperlipidemia cause ischemic heart and cerebral diseases. In addition, hypertension is usually coupled with diabetes. Therefore, in diabetic patients whose condition has been complicated with hypertension, antihypertensive drugs should not only control blood pressure, but should also not adversely affect glucose and lipid metabolism. With this in mind, we studied the hypotensive effect of arotinolol, an α·β-blocker, and its effect on glucose and lipid metabolism.
206 patients in 56 hospitals received 20mg of arotinolol (Almarl®) twice a day for 24 weeks. The blood pressure and heart rate were measured every 2-4 weeks and fasted blood glucose (FBG), total cholesterol (T-Ch), triglyceride (TG), HDL-cholesterol (HDL-Ch), HbA₁ and HbA_1C were determined every 4 weeks.
The subjects were 206 diabetic patients with hypertension, 127 of which (=group A) received arotinolol only, and 79 of which (=group B) received a combined therapy with other antihypertensive drugs. The results were as follows.
1) Both in group A and B, arotinolol significantly reduced systolic (SBP), diastolic (DBP) and mean blood pressure (MBP) after 2 weeks and thereafter. In group A the percentages of patients whose SBP and DBP recovered to normal levels (below 140mmHg and below 85mmHg respectively) were 33.6% and 53.6%, respectively.
2) Arotinolol also significantly decreased blood pressure in patients whose condition had been complicated with diabetic nephritis.
3) In terms of glucose metabolism, although arotinolol showed a tendency to slightly increase FBG, it did not significantly increase HbA₁ and HbA_1C.
4) Arotinolol did not significantly change T-Ch, TG and HDL-Ch.
5) Arotinolol produced no side-effects and was shown to be a safe drug.
On the basis of the results noted above, we concluded that arotinolol is a useful antihypertensive drug which does not adversely effect glucose and lipid metabolism in diabetic patients with hypertension.

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We assessed atherosclerotic lesions (AL) of the thoracic aorta and its stiffness in 17 patients with familial hypercholesterolemia (FH; 51±9 ys) and 21 normal subjects according to age by conducting biplane two-dimensional transesophageal echocardiography (TEE: 5MHz). The descending aorta was divided into 4 portions with equal lengths and the degree of AL was classified into 4 categories by TEE depending on the severity of AL: Score-1=intimal thickening, 2=atheromatous plaque, 3=calcified plaque associated with acoustic shadowing behind the lesion. The AL in the descending aorta (DAo) was scored. In all patients with FH, AL with a score higher than 1 was frequently observed in the aortic arch and the DAo; however, none of control subjects had AL with a higher score than 1. In 6 of all FH patients (35%), AL with a higher score than 3 was found in the aortic arch and the DAo rather than in the ascending aorta. The total atherosclerotic score (TAS: sum of scores obtained from each portion) was significantly higher in the FH (3.8±1.5) than in the control subjects. We also measured instantaneous dimensional (D) changes of the DAo in a cardiac cycle by conducting a TEE M-mode echography while monitoring the 2-D view. The stiffness parameter (β=ln (Ps/Pd)/(D_max-D₀)/D₀, where Ps: systolic blood pressure, Pd: diastolic blood pressure, D_max: maximum aortic dimension during the ejection period, D₀: minimum aortic dimension during the pre-ejection period) in the FH (subjects (10.2±4.3) was significantly greater than in the control subjects (5.1±1.2, p<0.001) although there were no significant differences in the D₀ of the control subjects, indicating increased aortic stiffness in the FH subjects. In both control and FH subjects, β was correlated with age (r=0.61, p<0.01, r=0.65, p<0.01, respectively). In the FH subjects, β or TAS was correlated well with the total cholesterol level (r=0.63, p<0.05, r=0.65, p<0.01, respectively). Thus, TEE with a biplane probe proved to be a reliable method to evaluate the well property of the thoracic aorta. Even in the relatively younger population of the FH, group, the incidence of AL in the thoracic aorta was significantly higher than in the control subjects. Moreover, this higher incidence of AL was accompanied by increased aortic stiffness.

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LDL-apheresis with a dextran sulfate-cellulose adsorption column (Liposorber) is a popular method for treating hypercholesterolemia. In the present study, we analyzed various lipoprotein particles which were adsorbed during the treatment of hypercholesterolemia using a Liposorber, and in an in vitro column operation.
LDL apheresis with a 3-liter plasma processing capacity was conducted on patients with hypercholesterolemia. In addition, 3ml each of sera from normolipidemic individuals and patients before or after LDL apheresis were allowed to pass through a dextran sulfate-cellulose column with a bed volume of 7ml; or were incubated with the absorbent body to evaluate the concentration of lipids and apoproteins, the composition of lipoprotein particles, size, and the effects on Lp (a) and RLP. The particle size was determined under electron microscopy; Lp (a), using a kit by Biopool; and RLP, with an anti-apo B-100 monoclonal antibody adsorption column.
Compared with the data before LDL apheresis (100%), the samples were examined during the processing of 1.5-liter plasma (a mid-stage) and during the processing of 3-liter plasma (postapheresis). The results were: plasma chol., 51% and 30%; plasma TG, 40% and 27%; plasma PL, 57% and 37%; apo B, 78% and 44%; apo E, 41% and 28%; and apo A-I, 73% and 68%. Both Lp (a) and RLP showed a marked reduction through the process [Lp (a); (before) 207.6mg/dl (100%)—(midstage) 110mg/dl (53%)—(post-apheresis) 79mg/dl (38%); RLP; (before) 59.4mg/dl (100%)—(midstage) 12.9mg/dl (21%)—(post-apheresis) 10.5mg/dl (17%)]. With the in vitro column operation, more than 90% of the Lp (a) and RLP were removed from the sera. Furthermore, the sizes of the particles adsorbed in the column appeared to be more heterogeneous and larger at the start than at the completion of the apheretic procedure. The apoprotein composition of the bound fraction of chylomicron (SF>400) was determined by SDS PAGE. The fraction of chylomicron bound to the absorbent body contained apo B-48.
It was concluded that the dextran sulfatecellulose column provides superior LDL-C adsorption removal; and is simultaneously effective in adsorbing Lp (a), RLP (presumably remnant particles), and apo B-48-containing particles.

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We investigated the effects of double-membrane filtration with hollow-fiber membranes made of different artificial materials and the low-density lipoprotein (LDL)-adsorbant dextran sulfate cellulose column on coagulation-related proteins and complement components in order to evaluate the hemocompatibility of these instruments. All the membrane filters showed a similar seiving effect which depended on the molecular weight of proteins. In the double membrane filtration system, free protein S, protein C, antithrombin III and α₁-antitrypsin were returned to intracorporeal circulation though α₂-macroglobulin and fibrinogen were almost completely removed from the circulation. C4b-binding protein (C4BP)-protein S complex was trapped by the second membrane. It was even trapped by the first membrane, which was made of materials that activate the classical pathway of the complement system. The dextran sulfate column adsorbed C4BP-protein S complex, but free protein S was recovered in the eluate.

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A high concentration of plasma Lp (a) is a risk factor of ischemic heart disease, and the Lp (a) level is genetically determined. Recently, it has been shown that in patients with NIDDM, high Lp (a) levels (high-Lp (a)) are observed more frequently than in the normal population. However, the cause of this phenomenon has not yet been fully investigated. Therefore, we determined the Lp (a) concentrations in 195 patients with NIDDM, 20 patients with IDDM and 195 normal subjects, to examine the correlation of Lp (a) concentration with clinical characteristics, fibrinolytic factors, and the levels of lipids and apolipoproteins. The results showed that the Lp (a) concentrations in patients with NIDDM (the mean±SD: 177±73mg/l) were significantly higher than those in normal subjects (115±101mg/l). The incidence of high-Lp (a) (≥250mg/l) in these patients (27%) was also higher than that in the normal group (11%). Between the two groups of high-Lp (a) (143 cases) and low-Lp (a) (<250mg/l, 52 cases) in patients with NIDDM, there were no differences in the plasma glucose level, HbA_1c, type of therapy or fibrinolytic factors. Meanwhile, in patients with NIDDM, the Lp (a) concentrations were correlated with the levels of total cholesterol, LDL-C and apo B, and the incidence of high-Lp (a) increased with the grade of proteinuria. Furthermore, the Lp (a) concentration was in no way correlated with the creatinine serum level, but was significantly correlated with the amount of urinary protein (r=0.508, p<0.01). In follow-up studies on 81 NIDDM and of IDDM patients over 1-19 months, the Lp (a) concentrations of most of the patients did not change significantly. However, the Lp (a) levels in 6 patients with nephrotic syndrome were higher (447±356mg/l), although these levels were lowered (294±187mg/l) when the proteinuria was improved by the treatment. We suggest that there may be a secondary high-Lp (a) besides the inherited high-Lp (a) in patients with NIDDM. On the basis of the relationships between Lp (a) and total cholesterol, LDL-C, apo B or urinary protein, we believe that this secondary high-Lp (a) may result from the hyperproduction of protein in the liver compensating for the loss of protein into the urine. The studies of 14 families (53 members), whose probands had NIDDM and high-Lp (a), showed that six families had no members with high-Lp (a) except the proband, and that five of the six probands were associated with proteinuria. This family study also noted the existence of high-Lp (a) secondary to proteinurua. In the diabetic patients with cerebrovascular disease and coronary heart disease, high-Lp (a) was more frequent than in those without these complications. In diabetics, not only inherited high-Lp (a), but also secondary high-Lp (a) may be risk factor leading to atherosclerosis.

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It is clear that peroxide damage to tissues could be of general significance in the tissue damage frequently associated with diabetes mellitus. Oxidative damage has been implicated in the pathogenesis of diabetic complications. This damage may be mediated by normophysiological responses to abnormally elevated levels of peroxide. Therefore, the possibility of superoxide production by the glycated fibrinogen was investigated. The findings indicated that glycated fibrinogen reduced cytochrome c and nitroblue tetrazolium. This reduction was inhibited by superoxide dismutase, which indicates that glycated fibrinogen produces superoxide in vitro. To evaluate possible new approaches to the prevention of diabetic complications, the effect of bifemerane hydrochloride (4-(O-Bezylphenoxy)-N-Methylbutylamine hydrochloride) on the inhibition of superoxide production was investigated in vitro. This agent inhibited the reduction of cytochrome c by glycated fibrinogen. But the effective concentration in vitro is much higher than that of the serum concentration which was administrated by oral dosage. Therefore, the effect of bifemerane hydrichloride on reducing the vascular complications of diabetes in vivo requires further research.

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