抄録
We investigated the effects of exercise on endothelial function in Dahl salt-sensitive rats with risk factors for atherosclerosis, i.e. hypertension and/or hypercholesterolemia. We randomly assigned 174 rats to four experimental diet groups: (MF) control diet; (S) high-salt diet; (C) high-cholesterol diet; and (SC) combination of high-salt and high-cholesterol diet. The rats took these diets ad libitum. Each group was further assigned to two exercise conditions: sedentary group (SD) and exercise group (EX), swimming for 1 hour/day, 5 days/week. Chronic swimming exercise and experimental diet were started at the same time and continued for 8 weeks. After physiological examination every 2 weeks, we observed the distribution of NO and superoxide production in endothelial cells around aorto-renal bifurcation by using confocal laser-scanning microscopy. We evaluated the endothelial function with the oxidative stress index, the ratio of superoxide production to NO production. Chronic swimming exercise decreased the physiological risk for atherosclerosis, growth rate of body weight in all diet groups significantly, blood pressure in MF and C significantly, tended to decrease trigriseride, and increased HDL in all diet groups significantly. There was no difference in the oxidative stress index between artery portions, risk factors, and sedentary and exercise, but, decrease of NO production was related to atheroma prone portion. Therefore NO production may more contribute to the localization of atherosclerosis than oxidative stress. [J Physiol Sci. 2006;56 Suppl:S131]
