[The age-related characteristics of the contractile function and of the calcium-transport system of the rat myocardium under conditions of restricted coronary perfusion].

In experiments on isolated rat heart, it has been shown that in old animals the sensitivity to restriction of the coronary perfusion increases whereas the resistance of the heart to this restriction decreases. It was established that incomplete reversible ischaemia causes significant changes in different steps of Ca2(+)-transporting system of the myocardium which are more evident in older animals and which presumably account for the increased sensitivity of cardiac muscle to ischaemia.