EXERCISE-INDUCED CORONARY ANGIOGENESIS - A REVIEW

Numerous studies have examined the effects of exercise training on cor onary angiogenesis. Although the conclusions drawn from these studies are sometimes conflicting, variabilities in training (magnitude, type and intensity), age and other factors need to be closely examined. Mos t studies on young animals indicate that capillary growth occurs provi ding that the training intensity is appropriate. Furthermore, there is evidence that growth of arteries and resistance vessels can occur as indicated by 1) direct measurements of vessels and 2) calculation of m inimal coronary vascular resistance during pharmacologically induced v asodilation. Although the mechanism(s) underlying exercise-induced ang iogenesis is unknown, mechanical events associated with increased flow and/or increased venous return, as well as resting bradycardia may se rve to trigger growth factors involved in mitogenic, migratory, and tu be formation of endothelial cells. In contrast, exercise training per se does not appear to enhance collateral Vessel growth. However, there is evidence that collateral growth is accelerated with training in an imals with coronary artery occlusion.