Search PubMed⌕ Search

Biomedical subjects

M Shinomiya

Publications and source records attributed to M Shinomiya.

103 records · Page 6Linked to original sources
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↗
PubMed1979

Studies of cholesterol esterase in rat arterial wall.

Cholesterol esterase activity was estimated in homogenates of rat arterial wall using radioactive cholesteryl oleate incorporated into phospholipid vesicles as a substrate. The labeled oleic acid was separated from the ester by addition of benzene-chloroform-methanol mixture. Under these conditions, two pH optima were found at about 4.5 and 7.5. Most of the activities at pH 4.5 and 7.5 were found in the lysosomal and microsomal fraction, respectively. No enzyme activity was detected when the substrate vesicles were prepared with phosphatidylethanolamine or sphingomyelin, but the activity was higher when the substrate vesicles were prepared with phosphatidylserine and highest when they were prepared with phosphatidylcholine. The relationship between enzyme regulation and lipid deposition in the arterial wall is discussed.

Animals↗
PubMedDate not supplied

Studies on cholesterol ester hydrolysis in artificial lipid mixtures.

Cholesterol ester is present in lipid deposits in atherosclerotic lesions, such as fatty streaks, fibrous plaques and complicated lesions. The possibility of hydrolysis of cholesterol ester in lipid deposits and its mechanism were examined by studying the effects of the various components of lipid deposits on cholesterol ester hydrolysis. Studies were carried out using artificial lipid samples prepared by sonication of mixtures of the components of lipid deposits. Results suggested that phospholipids, especially phosphatidylcholine, play an important role in the hydrolysis and that alteration of lipid components, other than cholesterol ester, influences cholesterol ester hydrolysis in lipid deposits.

Animals↗
PubMedDate not supplied

Effects of pindolol on serum lipoproteins and postheparin lipolytic activities in hypertensive patients.

Thirty-four hyperlipoproteinemic, hypertensive patients received 5 mg of pindolol twice daily for 12 weeks. During pindolol administration, there were significant decreases in serum triglyceride levels and increases in high-density lipoprotein cholesterol (HDL-C) levels, while total cholesterol levels did not change. Serum levels of very-low-density lipoprotein (VLDL) triglyceride and VLDL cholesterol decreased over time as HDL-C increased. There was a significant increase in low-density lipoprotein cholesterol at week 12. Apolipoprotein (apo) A-I, A-II, and B levels did not change during pindolol administration, but apo C-II, C-III, and E levels decreased significantly. Lipoprotein lipase activity in heparin-treated plasma was significantly higher after pindolol administration. The results suggest that the reduction in triglyceride levels and increase in HDL-C after pindolol are partly a response to an increase in the hydrolysis of VLDL resulting from an increase in lipoprotein lipase activity.

Apolipoproteins↗
PubMedDate not supplied

Serum lipid levels in hypertensive patients during captopril treatment.

Captopril (37.5 mg daily) was administered to 64 hypertensive patients for 16 weeks. During treatment, systolic and diastolic blood pressures decreased significantly (from means of 164/98 mmHg before treatment to 150/90 mmHg at four weeks and 142/86 mmHg at eight weeks; P less than 0.001), but serum levels of total cholesterol, triglycerides, lipoprotein cholesterol, lipoprotein triglyceride, and apolipoproteins showed no significant changes. Scores on the atherogenic index did not change. Patients with high initial total cholesterol levels and low high-density lipoprotein cholesterol levels tended to improve their lipid levels. It is concluded that captopril does not adversely affect serum lipoprotein metabolism.

Apolipoproteins↗
PubMedDate not supplied

A case of aortic septal defect, associated with patent ductus arteriosus and aberrant right subclavian artery.

This report describes an operation, successfully performed by the authors, on an aorta septal defect (A-P Window) associated with patent ductus arteriosus (PDA) and aberrant right subclavian artery (ARSA). When an A-O Window is complicated by PDA and ARSA, preoperative diagnosis is often difficult. It is often mistaken for a large PDA and ARSA. Therefore at the time of operation of a large PDA and ARSA, it is necessary tao keep artificial heart-lung machine ready so that the A-P Window can be corrected at the same operation if necessary. In this case, the aortopulmonary communication was closed directly by transpulmonary approach under profound hypothermia with extracorporeal circulation after the division of ductus arteriosus and the dissection and mobilization of the stenotic esophagus from surrounding tissues of the ARSA. The division of the ARSA was not carried out, because patient was asymptomatic. The A-P Window associated with PDA and ARSA has apparently not been reported.

Ductus Arteriosus, Patent↗