Coronary Flow Response to Vasodilators in Isolated Hearts Cold Perfused for One Day with Butanedione Monoxime

Objectives Impaired tissue reperfusion may be an important limiting factor for long-term hypothermic cardiac preservation. Cardiac function and recovery of coronary responses to endothelium independent and dependent vasodilators were tested before and after one day of preservation by cold perfusion with a normal extracellular solution containing the contraction uncoupler 2,3, butanedione monoxime (BDM) with or without reperfusion with nitroprusside (NP) plus adenosine (Ade) or plus the nucleoside transport inhibitor, nitrobenzylthioinosine (NBTI).Methods Guinea pig hearts (n = 70) were isolated and perfused at constant pressure during normothermic conditions (37°C). Groups 1 and 2 were perfused for 8 hrs without cold perfusion (time control); group 2 was also infused with arginine vasopressin (AVP) for 6 hrs; groups 3–5 were infused with BDM before, during, and initially after 22 hrs of constant, low flow hypothermic (3.8°C) perfusion; group 3 was also infused with NP and Ade, and group 4 with NP and NBTI...