PubMed Health⌕ Search

Biomedical subjects

M Mizobuchi

Publications and source records attributed to M Mizobuchi.

70 records · Page 4Linked to original sources
PubMed1984

[Effect of mazindol on free fatty acid metabolism in the brain of rats].

The effects of mazindol which is known as a anorexigenic agent on the free fatty acid metabolism in the brain were studied. One-half mg of mazindol was orally administered to rats weighing 500 g for 5 days. Body weight was reduced by 10%, compared to the control. Serum levels of free fatty acid, triglyceride, total cholesterol and phospholipid were decreased. The effect of mazindol on the incorporation of [1-14C] palmitic acid into various lipids in the brain were studied. When mazindol (5 mg) was administered one hr before injection of [1-14C] palmitic acid to the internal carotid artery of rats ad libitum, incorporation of [1-14C] palmitic acid into free fatty acids in the cerebrum and diencephalon was lower than that of the control, but incorporation into phospholipid and triglyceride were higher than that of the control. When mazindol was injected into fasting rats, incorporation into free fatty acid in cerebrum and diencephalon was increased compared with the control, and the incorporations into phospholipid and triglyceride were decreased.

Animals↗
PubMed1983

Lipid metabolism in the aorta of daunomycin-induced nephrotic rats.

Several enzyme activities involved in lipid hydrolysis (acid and neutral cholesterol esterase and lipase) or synthesis (acyl-CoA synthetase, acyl-CoA: cholesterol acyltransferase and cholinephosphotransferase) were assayed in the aortas of rats with nephrosis induced by daunomycin and of rats fed on high cholesterol diet. In nephrotic rats activities of some enzymes involved in lipid hydrolysis, but not in synthesis, were increased. On the contrary, in rats fed on high cholesterol diet, the activities of all enzymes involved in lipid synthesis were significantly increased, with some increase in those involved in lipid hydrolysis. In nephrotic rats fed on high cholesterol diet all enzyme activities were markedly increased. From the view point of accumulation of cholesterol ester (CE), the ratio of hydrolysis of CE in lysosomes to CE incorporated from the blood and the ratio of hydrolysis of CE to reesterification of free cholesterol in microsomes were considered to be important. From this point of view, nephrotic hyperlipidemia was not so atherogenic as hyperlipidemia induced by the diet. The role of serum high density lipoproteins in lipid metabolism in the aorta was discussed.

Animals↗
PubMed1982

N-acetyl-L-aspartic acid, N-acetyl-alpha-L-aspartyl-L-glutamic acid and beta-citryl-L-glutamic acid in human urine.

N-Acetyl-L-aspartic acid (NA-Asp), N-acetyl-alpha-L-aspartyl-L-glutamic acid (NA-Asp-Glu) and beta-citryl-L-glutamic acid (beta-CG), which are known to occur in the brain, have been isolated from human urine. Their identities were proved by comparing them with synthetic NA-Asp, NA-Asp-Glu and beta-CG using electrophoretic and chromatographic methods and by acid hydrolysis. A method was developed for the quantitation of NA-Asp, NA-Asp-Glu and beta-CG in human urine. It consists of ion-exchange chromatography followed by gas-chromatographic analysis. The amounts of urinary excretion of NA-Asp, NA-Asp-Glu and beta-CG were 41.2 +/- 10.1 (n = 27), 20.8 +/- 9.6 (n = 27) and 30.2 +/- 13.2 (n = 21) mumol/g creatinine in adult males, and 62.2 +/- 16.3 (n = 27), 24.0 +/- 8.2 (n = 27) and 40.5 +/- 21.1 (n = 24) mumol/g creatinine in adult females, respectively.

Adult↗
PubMed1982

Determination of peptidoaminobenzophenone (2-o-chlorobenzoyl-4-chloro-N-methyl-N'-glycylglycinanilide) and its metabolites in human plasma by glass capillary gas chromatography negative ion chemical ionization mass spectrometry--1.

A highly sensitive and selective glass capillary gas chromatographic negative ion chemical ionization mass spectrometric assay was developed to measure peptidoaminobenzophenone(2-o-chlorobenzoyl-4-chloro-N-methyl-N'-glycylglycinanilide) and its metabolites; chlorodiazepam, chlorodesmethyldiazepam and lorazepam in human plasma. As peptidoaminobenzophenone underwent pyrolysis during gas chromatography, it was converted to a thermally stable aminoquinolone. Internal standards for these compounds were the respective deuterium labelled compounds. Calibration curves were prepared for the range of 1-100 ng ml-1. Interference by endogenous substances was negligible in the isobutane negative ion chemical ionization mode in contrast to the electron impact or positive ion chemical ionization mode. This method was used to determine the plasma levels in humans following oral administration of two 5 mg doses.

Anti-Anxiety Agents↗
PubMed1982

Lipid metabolism in arteriosclerotic arterial wall of rats.

Arteriosclerotic lesions were formed in rat aorta by the administration of vitamin D2, a high-fat diet and a thyroid suppressing agent. This treatment increased the serum total cholesterol level to 12 times the control level. In the arteriosclerotic lesions that were induced the activities of lysosomal enzymes, such as acid phosphatase and acid lipase, were higher than in controls, that of acid cholesterol esterase was decreased, those of microsomal lipid-synthesizing enzymes--such as acyl-CoA synthetase and cholesterol ester synthesizing activity--were increased and that of neutral cholesterol esterase was decreased. These data suggest that lipid metabolism in arteriosclerotic lesions was changed, resulting in the accumulation of cholesterol esters in the aorta. Administration of high-fat diet and thyroid suppressing agent also increased the serum cholesterol levels to 12-fold the control level, but did not induce arteriosclerotic lesions. After this treatment the activities of hydrolyzing enzymes, such as acid and neutral cholesterol esterase and lipase, in the aorta increased, but the activities of lipid synthesizing enzymes also increased. These data suggest that lipid metabolism in the aorta in this condition changed to compensate for the large influx of serum lipids and to prevent arteriosclerosis. The roles of the serum lipid level, cell injury and lipid metabolism in the aorta in forming arteriosclerotic lesions are discussed on the basis of these results.

Animals↗
PubMed1982

Incorporation of [1-14C[palmitic acid into neutral lipids and phospholipids of rat cerebral cortex in vitro.

Incorporation of [1-14C]palmitic acid into neutral lipids and phospholipids of rat cerebral cortex was examined in vitro in normal Krebs--Ringer bicarbonate buffer containing 3% (wt/vol) albumin and 0.75 mM palmitic acid. Under standard assay conditions, radioactivity in the triacylglycerol fraction increased rapidly during the first 30 min, and then decreased after 60 min, with corresponding increase in radioactivity in phosphatidyl choline, phosphatidyl ethanolamine, and a fraction of phosphatidyl inositol plus phosphatidyl serine. Diacylglycerol was shown to be an intermediate metabolite. Radioactivity increased in triacylglycerol, and decreased in phosphatidyl choline and phosphatidyl ethanolamine throughout incubation under N2 gas. In the fraction of phosphatidyl inositol plus phosphatidyl serine, radioactivity decreased after 30 min during incubation under N2 gas. A possible acylation--deacylation cycle, in which triacylglycerol could be a source of free fatty acids for phospholipids, is discussed.

Animals↗
PubMed1982

Effect of tocopherol deficiency on lipid metabolism in arterial wall of spontaneously hypertensive rats on normal and high cholesterol diets.

Lipid metabolism in the arterial wall of spontaneously hypertensive rats (SHR) fed on tocopherol-deficient diet, high-cholesterol diet or both was studied. Serum tocopherol was greatly decreased in tocopherol-deficient SHR. Lipoperoxide, determined as thiobarbituric acid-reactive substances, was higher in tocopherol-deficient SHR than in normal SHR. Tocopherol-deficient SHR showed a decrease in acid cholesterol esterase activity, but no change in neutral cholesterol esterase, acid and neutral lipase, acyl CoA synthetase, cytidine-diphosphate choline-1-2-diacyl glycerol choline phosphotransferase (CPT) or triglyceride synthesizing activity.

Animals↗
PubMed1982

Lipid metabolism in the aorta and the brain microvessels of rabbits on high cholesterol diet.

The characteristics and properties of lipid metabolism in the aorta and the brain microvessels of rabbits were investigated to clarify the role of lipid metabolism in formation of atherosclerosis. In rabbit aorta, cholesterol esterase and lipase each had an acidic and a neutral optimum pH, whereas acyl-CoA synthetase, acyl-CoA: cholesterol acyltransferase, triglyceride synthesizing activity and choline phosphotransferase each had one neutral optimum pH. These pH optima were similar to those in rats. High cholesterol diet induced atheromatous lesions in the aorta, but not in the brain microvessels. In atheromatous aorta, the acid lipase and acid phosphatase activities were higher than in controls, but not the acid cholesterol esterase activity. Moreover the activities of neutral lipase, acyl-CoA synthetase, acyl-CoA:cholesterol acyltransferase, triglyceride synthesis and choline phosphotransferase were increased, but neutral cholesterol esterase activity was normal. These data suggest that lipis metabolism in the atheromatous aorta is changed in a manner favoring accumulation of lipids, especially cholesterol esters. In controls, most of the above enzyme activities in the brain microvessels were higher than those in the aorta. However, these enzyme activities in the brain microvessels were not changed by cholesterol feeding. Thus it is suggested that the properties of lipid metabolism in the aorta and brain microvessels, including permeability of lipoproteins into the vessel walls, are important in formation of atherosclerosis in addition to the serum factors.

Animals↗
PubMed1981

Studies on lipase in rat brain.

Lipase activity was measured in homogenates of rat cerebral hemispheres using radioactive glycerol trioleate emulsified with Triton X-100 as substrate. The labeled oleic acid was separated from the ester with a methanol-chloroform-heptane mixture. Under these assay conditions, the activity showed pH optima at about 5.5 and 7.5. The final products of these lipase activities were suggested to be free fatty acid and glycerol.

Animals↗
PubMed1981

Regulation of lipase activities in rat brain in vitro.

Regulation of acid and neutral lipase activities in rat brain was examined in vitro. Both activities were decreased by SDS, CuCl2 and ZnCl2 and by delipidation. The neutral lipase activity was also markedly reduced by N-ethylmaleimide and PbCl2. The activity of delipidated preparation was increased by addition of phosphatidyl choline at both pH 5.5 and 7.5 and by phosphatidyl serine at acidic pH value. Pretreatments of the enzyme preparation with phospholipase A and trypsin reduced the lipase activities at both pH values. It is suggested that phospholipids play an important role on lipase activity in brain.

Animals↗
PubMed1980

Effects of tocopherol deficiency on lipid metabolism in the arterial wall of rats on normal and high cholesterol diets.

The effects of dietary tocopherol deficiency on arterial wall enzymes involved in lipid synthesis and hydrolysis were studied in rats receiving normal diets and diets supplemented with 1% cholesterol. Arterial wall lipase and cholesterol esterase were associated with both the lysosome and microsome fractions, whereas acyl CoA synthetase, triglyceride synthesizing activity, cholesteryl ester synthesizing activity and cytidine diphosphatecholine-1,2-diacyl glycerol choline phosphotransferase (CPT) were found mainly in the microsomal fraction. When tocopherol was depleted from either the normal or high cholesterol diets, the following changes occurred in the arterial wall: (1) increase in thiobarbituric acid reactive substances; (2) decrease in lysosomal acid lipase and acid cholesteryl esterase; (3) decrease in the microsomal enzymes, acyl CoA synthetase, triglyceride synthesizing activity, cholesteryl ester synthesizing activity, neutral lipase and neutral cholesteryl esterase; and (4) increase in microsomal CPT. The results of these studies suggest that dietary tocopherol plays an important role in both lipid synthesis and degradation in the arterial wall, and the results may account for the accumulation of lipids and lipoperoxides in atherosclerotic lesions.

Animals↗
PubMedDate not supplied

HTLV-I-associated myelopathy (HAM) in Tokushima Prefecture--geographical and clinical studies in an area between endemic and non-endemic areas of HTLV-I infection.

The geographic distribution and clinical features of patients with HTLV-I-associated myelopathy (HAM) in Tokushima prefecture were investigated. Nine patients were found prior to December 1990. The minimal prevalence was estimated as 1.1 per 100,000 in the general population, and 1 per 1,309 in HTLV-I-seropositive persons. Seven patients were found in the southern district facing the Pacific Ocean, but only 1 patient each was found in the northern and western districts. The age at disease onset ranged from 15 to 53 yr (average 33 yr). The ratio of male to female patients was 1:8. Adult T cell leukemia was associated with HAM in 1 patient, and Hashimoto's disease in 2 patients. These cases have not been reported previously. The route of transmission of HTLV-I was concluded to be vertical in 4 patients and horizontal in 4 patients, but was uncertain in 1 patient. No evidence of transmission by blood transfusion was found in these patients.

Adult↗