SUMMARY It is possible that one of the consequences of regular physical activity could be a change in vascular metabolism. We studied the effects of regular swimming activity on specific activities of aortic hydrolases of male rats. Enzymes included: neutral a-glucosidase and lysosomal /3-galactosidase, JV-acetyl-/}-glucosaminidase, cathepsin C, acid a-glucosidase, and acid cholesteryl esterase. After 8 or 16 weeks of a 1-hour/day swimming protocol, specific activities of four of the six aortic enzymes studied were increased over control levels, increases ranging from 7 to more than 42%. Acid cholesteryl esterase was one of the enzymes most affected by the exercise, increasing 25-30% above control levels. An 8-week sedentary period, after 8 weeks of a swimming regimen, resulted in return of the activity of acid cholesteryl esterase, but not those of the other hydrolases, to control levels. Decreases in body weight, blood pressure, and serum lipid levels also occurred in the swimming rats. Weight reduction per se was excluded as an explanation for the increases in aortic enzymes or decrease in serum cholesterol found with swimming. These findings show that regular physical activity is yet another factor with discrete and significant effects on the catabolic activity of vascular tissue.
Ore Res 45: 548-553, 1979VIGOROUS exercise appears to be associated with a reduced prevalence of death from coronary heart disease in man (Paffenberger and Hale, 1975); less extreme exercise has not been so clearly related. Apart from the question of degree of exercise, it remains uncertain whether exercise itself is protective or whether it results in a favorable clustering of other factors associated with reduced risk. Among the latter are a decreased total serum cholesterol level (including decreased low density lipoproteins and increased high density lipoproteins), a decreased serum triglyceride level (Lopez-S et al., 1974;Fletcher and Cantwell, 1974;Wood et al., 1976;Cantwell, 1978), reduced systolic and diastolic blood pressure levels (Scheuer and Tipton, 1977), and increased vital capacity (Kannel, 1967). Similar decreases in serum lipids and blood pressure with swimming or running activity have been described for the rat (Papadopolou° et al., 1969;Tipton et al., 1977).We recently (Wolinsky and Fowler, 1978) have emphasized the importance of understanding the direct effects of putative risk factors for vascular disease on cellular metabolism of the blood vessel wall in addition to noting the levels of certain circulating lipoprotein classes, the blood pressure