Role of Endothelin-A Receptors in Ischemic Contracture and Reperfusion Injury

Rat isolated hearts perfused at constant pressure, subjected to ischemia (reduced flow to 0.2 mL x min(-1) x g(-1)) and reperfusion

Infusion of ET(A) receptor-selective antagonist PD 155080 (50 nmol/L), ET(A)/ET(B)-nonselective antagonist PD 142893 (200 nmol/L), ET(B) receptor-selective antagonist BQ-788 (20 nmol/L), exogenous ET-1 (100 pmol/L), HOE 642 (10 micromol/L), nicardipine (30 micromol/L), or Sp-8-pCPT-cGMPS (10 micromol/L) during the ischemic phase

Untreated/control ischemic rat hearts

Extent and time-to-onset of contracture in ischemia, left ventricular developed pressure (LVDevP), coronary flow (CF), and diastolic relaxation during reperfusionsurrogate