Stimulation of σ1 receptors alleviates reperfusion-induced myocardial stunning

In vivo or in vitro administration of a sigma(1) receptor agonist d-SKF 10.047 (1 mg/kg intravenously or 10 mg/l in vitro) promoted an increase in the resistance of isolated perfused rat heart to ischemia/reperfusion injury. Both in vivo and in vitro stimulation of sigma receptors prevents the development of reperfusion contracture and creatine kinase release and increases the developed pressure, double product, +dP/dt, and -dP/dt in the left ventricle. Activation of sigma receptors has no significant effect on the occurrence of reperfusion arrhythmias ex vivo. Stimulation of cardiac sigma receptors is proposed to prevent myocardial stunning.