[Vascularization of the myocardium in rats during various motor regimens]

The author examined the vascularization of the myocardium by impregnation of argirophil fibers according to Gomori in white rats, undergoing various motor regimens: 8 animals traned by running for a period of 90 days, 8 animals were moveless for 90 days, 8 animals trained for 90 days and then were moveless for 50 days and 7 were controls. She compared the number of capilaries with the number of muscle fibers. There was statistically significant growth of the number of capillaries and their lumen was enlarged in the trained animals. There were no significant differences in the degree of vascularization of the myocardium in the moveless and control animals. In moveless animals after preliminary training the capillary bed of the myocardium was reduced and did not differ significantly from the control animal, but the lumen of all capillaries was still not reduced. Probably we could refer also the increase of the capillary lumen to the more stable adaptation changes together with the increase of the capillaries during raised functional requirements towards the myocardium.