高脂血症および高血圧症の改善効果における栄養の意義と運動の影響

Abstract

This study was designed to clarify the role of nutrition and physical exercise for preventing hyperlipidemia and hypertension.Sprague-Dawley strain rats were fed on a hypercholesterolemic diet containing 0.5% cholesterol and 0.25% Na cholate. Safflower oil suppressed hypercholesterolemia induced by dietary cholesterol when it was administered as the dietary source of fat. In contrast, administration of lard did not affect such hyperlipidemic state. Serum HDL cholesterol level had a tendency to increase in safflower oil group.Voluntary or forced exercise was loaded on the hypercholesterolemic rats. Both exercises significantly decreased serum triglyceride. Serum total cholesterol level was lowered by voluntary exercise rather than forced one. A reverse correlation was observed between serum total cholesterol and the running distance in voluntary exercise group when the animals were fed sucrose as carbohydrate source. The correlation was lower when starch or fructose was used in place of sucrose.Experiments were conducted to investigate the hypotensive principle (s) in Shii-ta-ke (Lentinus edodes) fruit bodies as well as in their mycelium on the blood pressure of spontaneously hypertensive rats (SHR). The extract of both fruit bodies and mycelia decreased the blood pressure of SHR. Safflower oil, Soya lecithin and highly purified eicosapentaenoic acid were tested in the same manner, and were found to exhibit obvious hypotensive activity.Healthy adult volunteers were supplied for 7 days several kinds of lipid-containing food. Combined administration of butter and eggs remarkably increased serum total cholesterol after 7 days, but single administration of each one did not. Blending oil of rice bran and safflower oil, in contrast, significantly decreased serum total cholesterol and increased HDL cholesterol.These results suggested a close relation between nutrition and exercise in the prevention of hyperlipidemia and hypertension.