Effect of dextran on the stability of isolated, perfused rat heart.

Stability of cardiac function and myocardial intracellular ionic composition was examined in the Krebs-perfused isolated rat working heart. Hearts perfused by a conventional Krebs solution showed stable contraction for 2 h, but during this period, intracellular ionic environment (Na, K, Ca) substantially changed. Addition of dextran to the perfusate inhibited, though not completely, this time-dependent deterioration and made the heart less vulnerable to the hypoxia-reoxygenation.