ABSTRACT
The effects of voluntary exercise on resting systolic blood pressure and vascular lesions of stroke-prone spontaneously hypertensive rats (stroke-prone SHR) were investigated with and without 1 % saline loading. Forty male stroke-prone SHR aged 7 weeks were assigned to one of 4 experimental groups. Each consisted 10 animals ; sedentary control (S), sedentary with 1 % saline loading (SS), exercised control (E), and exercised with 1 % saline loading (ES) . Animals were sacrificed at the 5 th week. In the prehypertensive phase, resting caudal arterial systolic blood pressure was significantly lower in the E group than in the S group. However, after being loaded with 1 % saline, the ES group showed higher resting systolic blood pressure than those of the SS group. In addition, the ES group revealed severer renal, myocardial, and cerebrovascular lesions than those of the rest of the groups.
ABSTRACT
In this study, we investigated the effect of exercise training on serum and liver chblesterol levels and on biosynthesis of liver cholesterol in rats. The training was carried out at low [Low-Ex, 60% max O<SUB>2</SUB> consumption (VO<SUB>2</SUB>) ] and high (High-Ex, 75% max VO<SUB>2</SUB>) intensities for 16 weeks. The energy expenditure was adjusted to be equivalent. The succinate dehydrogenase activities of gastrocnemius muscle in the Low-Ex group and High-Ex group were higher than that of control, 36% and 109% (p<0.05) respectively. The levels of total and high density lipoprotein cholesterol in serum were 14-26% lower than those of control, but no difference was detected between the trained groups. The activity of HMG-CoA reductase in liver microsome was significantly higher than that of control for both trained groups. However, the stimulation of this enzyme activity was not changed by training intensity.
ABSTRACT
The effect of a treadmill running program on the metabolism of cholesterol in serum and in arterial wall was studied in male Wistar rats, aged 7 weeks and weighing about 200 g- Rats were exercised on 6 days a week for 8 week, running 1, 000 m a day at 15 m/min. The trained rats gave the follwing evidence, as compared with the sedentary control animals:<BR>1. Remarkably lower body weight<BR>2. Significantly lower level of serum cholesterol-total, free, and LDL cholesterol<BR>3. Elevated in vivo incorporation of <SUP>14</SUP>C-mevalonate into serum cholesterol<BR>4. Enhancement of lecithin-cholesterol acyltransferase activity in serum<BR>5. Decrease in the amount of cholesterol in arterial wall cells<BR>6. Increase in in vivo incorporation of <SUP>14</SUP>C-mevalonate into arterial cholesterol.<BR>The results indicate that the excersice promotes the turnover of cholesterol in serum and arterial wall, repressing the accumulation of choleterol ester in arterial wall cells, and a prophylactic effect of the physical training for arteriosclerotic diseases has been suggested.
ABSTRACT
The effect of voluntary exercise training and influence of saline loading on blood pressure and cholesterol metabolism in rats were investigated in this study. Experimental animals used were male Wistar strain rats, aged 7 weeks old. These rats were allocated respectively into four groups, each of which consisted of 10 rats; sedentary control (SC), sedentary with 1 % saline loading (SS), training control (TC), and training with 1 % saline loading (TS) . In each of groups rats were sacrificed at the 10 th week.<BR>Following results were obtained in this study.<BR>1) The mean values of systolic blood pressure remained unchanged in all four groups, 2) serum and hepatic cholesterol levels were lowered by 10 weeks of exercise training, 3) the ratio of HDL-cholesterol to total cholesterol increased significantly in the training groups compared to that in the sedentary groups, 4) the incorporation of <SUP>14</SUP>C-acetate into liver cholesterol was significantly lower in the SS group than in the SC group, and 5) a direct correlationship was found between the increased exercise level and the incorporation of acetate into liver cholesterol in both TC and TS groups.
ABSTRACT
The effect of a treadmill running program on the metabolism of cholesterol in liver was studied in male Wistar rats, aged 7 weeks and weighing about 200 g. Rats were exercised on 6 days a week for 8 weeks, running 1, 000 m a day at 15 m/min. The trained rats gave following evidence, as compared with the sedentary control animals:<BR>1. Remarkable lower weight of body and liver<BR>2. Significantly lower level of total and free cholesterol in liver<BR>3. Elevated in vivo incorporation of<SUP>14</SUP>C-acetate and of<SUP>14</SUP>C-mevalonate into liver cholesterol<BR>4. Enhanced incorporation of<SUP>14</SUP>C-mevalonate into cholesterol by liver slice<BR>5. Increased activity of hydroxymethylglutaryl-coenzyme A reductase in liver<BR>6. Increase in cholesterol 7 a-hydroxylase activity in liver<BR>The results indicate that the exercise promotes the turnover of cholesterol in liver.