D-opioid receptors agonists prevent in vivo reperfusive heart injury in experiment

Rats anesthetized by chloralose were subjected to coronary artery occlusion (45 min) and, 5 minutes before reperfusion (120 min), treated intravenously with various d-opioid receptor agonists including deltorphin II at a dose of 150 nmol/kg; p-Cl-Phe-DPDPE at 150 and 1500 nmol/kg; DPDPE at 1500 nmol/kg; and BW 373 at 230 and 2300 nmol/kg. The response was evaluated by the ratio of the infarct zone (IZ) area to area at risk (AAR). It was found that deltotphin II at a dose of 150 nmol/kg, Cl-DPDE at a dose of 1500 nmol/kg, and BW373 at a dose of to 2300 nmol/kg reduced the IS/AAR ratio by 40% relative to control. Deltorphin II exhibited the protective effect at a 10 times lower dose than other drugs, which allows this d-opioid receptor agonist to be considered as prototype in creating medicines for the treatment of acute myocardial infarction.