Abstract
We studied the effects of the electrolyte composition (Na+, Ca2+) and amiloride, an inhibitor of Na+-Ca2+ exchange system on the postischemic reperfusion injury of rat hearts. The observed results are as follows: (1) Post-ischemic functional recovery increases with increased extracellular Na+ concentration of the initial reperfusate. (2) The recovery of cardiac performance is improved when the extracellular Ca2+ concentration of the initial reperfusate is reduced. (3) Amiloride, administered in the initial reperfustea, ameliorates cardiac damage in a dose-dependent manner (between 10-6M and 10-4M). It is concluded that the mechanism of post-ischemic reperfusion injury is dependent on the Na+-Ca2+ exchange system.
