Recovery of contractility and rhythmicity of isolated rat heart after prolonged total ischemia: Effect of number and duration of periods of preconditioning ischemia

Effects of single and repetitive episodes of total ischemia of different duration on recovery of cardiac contractile function and rhythmicity after 30 min of total ischemia and 20 min of reperfusion were studied on Langendorff-perfused rat hearts at 37 degrees C. Numbers of repetitive preconditioning episodes of ischemia were 3 and 5 and their duration 1, 2-3 and 5 min. Bouts of 5 ischemic episodes did not affect the process of restoration of contractility and rhythm. Single and triple episodes of 1-5 min of ischemia improved restoration of cardiac contractility while successions of 3 periods of 2-3 min of ischemia facilitated recovery of contractility and prevented reperfusion arrhythmias.