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Probucol significantly reduced high density lipoprotein (HDL)-cholesterol and apolipoprotein AI in rats. Hepatic uptake of radiolabelled human HDL3 increased significantly in vivo and in the isolated perfused rat liver preparation. In vivo, uptake of HDL3 by the adrenal glands also increased significantly. Hepatic cholesterol content in probucol-treated rats tended to increase, whereas newly synthesised cholesterol decreased significantly. The results of the present study suggest that enhanced uptake of HDL is one of the mechanisms of lowering serum HDL with probucol treatment.

Transport of L-proline, L-leucine and L-cysteine was studied in brush border membrane vesicles prepared from guinea pig ileum. Concentrative transport of L-proline, L-leucine and L-cysteine was obtained in the presence of an Na+ gradient from, outside to inside of the vesicles, which indicated contribution of either system A (alanine-preferring) or system ASC (alanine-, serine- and cysteine-preferring) to the transport. When Na+ was replaced by Li+, L-leucine and L-cysteine maintained the same concentrative transport. However, the concentrative transport of L-proline was markedly decreased by Li+ -for-Na+ substitution. Strong exchange properties of L-leucine transport via system L (leucine-preferring) was observed with brush border membrane vesicles, in which preloaded L-methionine could be exchanged with labeled L-leucine added outside the vesicles. These results suggest that the small intestine of the guinea pig possesses classical neutral amino acid transport systems such as systems A, ASC and L.

Pravastatin was administered to 20 patients with hyperlipidemia type IIa and IIb, for a period of 8 to 16 weeks at a daily dose of 10 to 20 mg, to investigate the effects on serum and biliary lipids. At the end of the treatment with pravastatin, the serum cholesterol level was significantly reduced, by 20%, compared with the control level. On the other hand, no significant differences were observed in serum high-density lipoprotein (HDL) cholesterol and triglyceride levels. Additionally, the administration of pravastatin did not change mole % compositions of biliary lipids, such as cholesterol, phospholipids, and total bile acids, as well as individual biliary bile acids. Consequently, there was not any significant change of the cholesterol saturation index. Based on the above results, our findings suggest that, for the treatment of hyperlipidemia, pravastatin is a highly effective cholesterol-lowering drug that does not affect biliary lipid metabolism.

A clonal ascited type cell, NAs-1, was obtained in culture from a mouse neuroblastoma C1300. The cells were adapted to anchorage-independently grow in the flask by the in vitro-in vivo alternate passage technique, and retained the ability of growing and producing ascites fluid when intraperitoneally injected into mice. Although the majority of growing cells in culture medium showed a small and round cell shape without any neuronal process, occasionally non-specific attachment onto the flask surface was observed, but devoid of the extrusion of processes. Karyotype analysis showed a homogeneous chromosome number, 40, with a marker chromosome [t(13:16)] and a minichromosome. Catecholamines, norepinephrine and dopamine, were found in the cell extracts and the contents of dopamine was particularly high as shown in another catecholaminergic neuroblastoma cell, N1E-115. Neuron specific enolase (γ-subunit) was also detected. The treatment of the cells by dibutyryl cyclic AMP, prostaglandin E1, or BL191 (phosphodiesterase inhibitor) induced the biochemical differentiation in terms of catecholamine and cyclic AMP contents, but failed to promote typical morphological differentiations including the extension of process or the significant promotion of adherence onto the flask surface.

The object of this study was to determine the effects of ursodeoxycholic acid administration on metastability in human gallbladder bile, as reflected by nucleation time. Bile samples from 10 patients with cholesterol gallstones who underwent preoperative ursodeoxycholic acid treatment exhibited a significantly longer median nucleation time (16 days) than those from 11 patients with cholesterol gallstones who received no preoperative treatment (4 days) (p less than 0.01). On the other hand, the median nucleation times of bile samples from 15 patients with noncholesterol gallstones and 24 patients without gallstones were 15 and 14 days, respectively. In addition, 3 mo of treatment with ursodeoxycholic acid significantly elevated the serum concentration of the antinucleating factor apolipoprotein A-I, from 133.3 +/- 12.3 to 148.6 +/- 13.2 mg/dl (p less than 0.05). These findings suggest that ursodeoxycholic acid retards cholesterol crystal nucleation, thereby inhibiting cholesterol gallstone formation. It is also possible that serum apolipoprotein A-I plays a role in this process.

A new ascites type neuroblastoma clone (NAs-1), which is characteristic both in anchorage-independent growth and catecholaminergic functions, attached on the monolayer culture of glioblasts and was subjected to morphological differentiation including the extrusion of neuronal processes. Other conventional neuroblastoma cells (Neuro2a, NS-20Y, and N1E-115) as well as NAs-1 in cocultured with normal glioblasts underwent a decrease in cell growth rates and DNA synthesis under the effect of the neuroblastoma growth inhibitory factor (NGIF) produced by glioblasts. After their NGIF production had been reduced by u.v. irradiation, glioblasts lost the growth-inhibitory and differentiation-promoting effects in coculture with NAs-1. The supplement of NGIF into u.v.-treated glioblasts restored the dose-dependent growth inhibition of NAs-1. The addition of nerve growth factor into the coculture system brought about neither the marked effect on growth inhibition of NAs-1 nor the morphological differentiation. The results imply a direct function of NGIF on the paracrine regulation of neuroblastoma cell growth in the coculture with normal glioblasts.

LCAT activity and mass were assayed simultaneously in 23 members of a new family case, revealing two homozygotes with a markedly low HDL--cholesterol level and ester cholesterol ratio. The LCAT mass in these patients was only 0.8 and 0.9 micrograms/ml, respectively (normal range 4.4-8.1) and their LCAT activity was 4 and 6 nM/ml/h 37 degrees C (normal range 60-120). Apolipoprotein (Apo) A-I and II levels were significantly low; however, apolipoprotein E tended to be high. In two-dimensional electrophoresis, apo A-I isoform visualized the increase of immature apo A-I; that is, A-I2. One subject showed the clinical characteristics of classic LCAT deficiency; however, the other, who was a vegetarian, showed corneal opacities and red cell deformity, but not proteinuria. This suggests that a low fat diet which decreases the level of atherogenic large LDL, may lead to a more favourable prognosis with a reduced risk for renal insufficiency. There were two different types of LCAT abnormality in this family series. Among the 10 examined paternal kindred of the proband who was one of two homozygotes, seven had a low LCAT mass but normal LCAT activity with the exception of one kindred who had a low mass and low activity. In contrast, among his seven maternal kindred examined, two had a low LCAT activity but normal mass.

Male golden hamsters fed a glucose diet as a model for cholesterol gallstone formation were used to investigate the effect of CS-514 on the lithogenicity of bile. Treatment with 0.05% (w/w) CS-514 in the diet for 1-4 weeks caused a decrease in plasma cholesterol and triacylglycerol levels. A marked increase in hepatic hydroxymethylglutaryl-CoA reductase activity in vitro and also an increased de novo cholesterol synthesis in the liver were induced by treatment with CS-514 for 1-4 weeks. The concentration of free cholesterol in liver microsomes and the cholesterol 7 alpha-hydroxylase activity were both decreased by treatment with CS-514 for 1 week, but were not affected by treatment for 4 weeks. The cholesterol output into bile and the lithogenic index of bile were double those of the control (glucose diet only) following treatment with CS-514 for 4 weeks, and the subsequent incidence of cholesterol gallstone formation was elevated. The content of free cholesterol and cholesterol ester in the liver was not affected by treatment with CS-514 for 4 weeks. These results suggest that long-term treatment with CS-514 causes a compensatory increase in the synthesis of hydroxymethylglutaryl-CoA reductase which leads to augmented hepatic de novo cholesterol synthesis and subsequent increased cholesterol output followed by an increase in the lithogenicity of bile. CS-514 apparently does not prevent cholesterol gallstone formation in those examples where the mechanism is thought to be due to augmented hepatic de novo cholesterol synthesis (type IV hyperlipidemia).

We measured aortic pulse wave velocity (PWV) in 168 male adult cases of various arteriosclerotic diseases. In order to evaluate the effects of age, smoking habits, alcohol intake, and blood pressure, we applied the least median of squares (LMS) regression which was considered to be very useful for data analysis. The results showed that PWV level increased with age. Furthermore smoking was associated with increasing PWV level and this effect was also related to age. We concluded that the PWV was valuable as an index of arteriosclerosis, and instead of the classical least squares method, LMS regression was very useful for analysis of medical data.

Lipids of HDL (high density lipoproteins) and their subfractions (HDL2 and HDL3), and LCAT activity (lecithin: cholesterol acyltransferase) were determined in hepatobiliary diseases without severe hyperbilirubinemia (less than 10 mg/dl). The decrease in major lipid constituents (cholesterol and phospholipids) of HDL was mainly attributable to the decrease in those of HDL3, except in some liver diseases of acute or severe stage (acute hepatitis in an acute stage and hepatoma) which were accompanied with a simultaneous moderate decrease in those of HDL2 and in fatty liver which showed a preferential decrease in those of HDL2. The LCAT activity also decreased in several diseases. Some of the hepatobiliary diseases, on the contrary, showed an increase in HDL-triglycerides (mostly in HDL3 and in some diseases also in HDL2) which might participate to some extent in secondary hyperlipidemia in the liver parenchymal diseases, although they were the minor lipid constituents of HDL. From results that HDL3- but not HDL2-cholesterol levels significantly correlated with serum total protein, albumin and choline esterase, it was suggested that the decrease in large constituents of HDL, particularly of HDL3, is caused by hepatocellular dysfunction which causes inhibition of protein and lipid syntheses in the liver in most of the hepatobiliary diseases except for fatty liver which has a preferential decrease in HDL2 lipids.