Search PubMed⌕ Search

Biomedical subjects

S Murano

Publications and source records attributed to S Murano.

48 records · Page 3Linked to original sources
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

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↗
PubMed1980

Effect of pantethine on cholesterol ester metabolism in rat arterial wall.

The total serum cholesterol level in rats fed on a high cholesterol diet (HCD) for 16 weeks was markedly higher than that in rats fed on a normal diet (ND), but pantethine reduced the increased level in rats fed on HCD (P less than 0.05). Acid cholesterol esterase activity (acid CEase) of arterial wall homogenates from rats fed on HCD was significantly lower than that of rats fed on ND (P less than 0.005). Acid CEase activity in the arterial wall of rats fed on HCD for 8 weeks and then ND for 8 weeks was less than that of rats fed on ND for 16 weeks. Acid CEase activity in the arterial wall was increased in rats fed on pantethine-containing diet. The ratio of cholesterol ester synthesizing activity to neutral cholesterol esterase (neutral CEase) activity was higher in rats fed on NCD than in those fed on ND. The ratio was lower in rats on the pantethine-containing diet than in those on NCD. The relationship between hypercholesterolemia and lipid metabolism in the arterial wall and effects of pantethine are discussed on the basis of these results.

Alanine Transaminase↗
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

Homologous recombination is elevated in some Werner-like syndromes but not during normal in vitro or in vivo senescence of mammalian cells.

Werner syndrome (WS) is a recessive genetic condition associated with markedly reduced replicative lifespans of cells in culture, high chromosomal instability in vivo and in vitro, and premature appearance of many characteristics of normal aging, including an increased incidence of cancer. We have monitored plasmid homologous recombination frequencies in diploid fibroblasts from 6 Werner or Werner-like syndrome patients, following transfection with a plasmid substrate containing 2 overlapping fragments of the TN5 Neor gene. Plasmid DNA recovered from these cells was then assayed for homologous recombination by (a) transformation of recA- bacteria to Ampr (indicating total viable plasmid) or Neor (indicating viable recombinant plasmid), and (b) by limited-cycle polymerase chain reaction (PCR) to co-amplify a recombinant fragment containing the overlap region, and a control region of the same plasmid, without bacterial transformation. Bacterial assay data indicated that recombination rates in 3 of the 6 WS strains were significantly elevated above normal controls; 4 of 6 appeared elevated by PCR assay. The highest-recombination WS strain showed evidence of reduced degradation of transfected plasmid DNA. For this small sample of WS strains, clinical severity of WS was not well correlated with recombination rate as determined by either assay (Pearson r = 0.78, not significant, for PCR assay); elevated recombination may, however, define a subset of WS at greatest risk for cancer and/or atherosclerosis. PCR assay of a hyperoxia-resistant HeLa cell line, displaying substantially increased chromosome breakage, indicated increased recombination between direct-repeat fragments. Nevertheless, elevated recombination in WS strains is unlikely to be secondary to impaired replicative capacity characteristic of WS cells, or to defective repair of chromosome damage which is increased in WS, since recombination in non-WS strains was unaffected by passage level or repeated UV irradiation.

Adult↗
PubMedDate not supplied

Comparison of the acute effects of acebutolol and propranolol on blood pressure, heart rate and hormonal changes during graded treadmill exercise in patients with essential hypertension.

The acute effects of propranolol and acebutolol on blood pressure, heart rate and hormonal changes during graded treadmill exercise were studied in patients with essential hypertension. Both of propranolol (2 mg i.v.) and acebutolol (10 mg i.v.) lowered the pre-exercise hemodynamic parameters and suppressed the elevation of systolic blood pressure, heart rate and pressure-rate product during exercise, but did not show any significant effect on diastolic blood pressure. Although these drugs increased plasma norepinephrine concentration (PNE) at rest and during moderate exercise, they failed to affect PNE at submaximal exercise. Plasma renin activity at rest and during exercise were more strongly suppressed by propranolol than acebutolol. Plasma aldosterone concentration was not affected by these drugs. Propranolol and acebutolol showed similar acute effects on blood pressure, heart rate and hormonal profiles at rest and during exercise within the doses used in this study. These results indicate that beta 1 adrenoceptor selectivity and intrinsic sympathomimetic activity may not play an important role in the acute antihypertensive effect at rest and during exercise and that both beta blockers have beneficial antihypertensive effects during exercise on patients with essential hypertension.

Acebutolol↗
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↗