INFLUENCE OF VARIOUS PRESERVATION SOLUTIO NS ON ENDOTHELIAL FUNCTION OF RAT CORONARY-ARTERIES

The effects of cold storage and type of preservation solution on coron ary endothelial function are not well established. Experiments were de signed to evaluate coronary endothelial-dependent relaxation after a 4 -hour cold (4 degrees C) storage in different preservation solutions. Rat hearts, mounted in the Langendorff apparatus, were arrested with a 10-minute perfusion of 4 degrees C crystalloid hyperkaliemic cardiopl egic solution (CHCS) (KCl 24 mEq/l) and stored for 4 hours in the foll owing preservation solutions : CHCS (n = 6), Krebs-Ringer solution (KR ) (n = 6), 0.9 % NaCl (NS) (n = 6) and the University of Wisconsin sol ution (UW) (n = 6). A fifth group (n = 6) was perfused and stored in U W solution. Endothelium-dependent and independent coronary artery vaso relaxations were respectively tested by infusing 5-hydroxytryptamine ( 5-HT) (10(-6) mol/l) and sodium nitroprusside (SNP) (10(-5) mol/l) bef ore and after the storage period. In hearts stored with CHCS or KR, co ronary artery flow increase to 5-HT and SNP infusions were not signifi cantly affected. However, in hearts preserved with NS or UW solutions, 5-HT coronary response was significantly decreased, indicating endoth elial dysfunction. In addition to these findings, coronary flow increa se to SNP infusion was decreased in the group perfused and stored with UW, suggesting smooth muscle dysfunction. These experiments suggest t hat 4-hour cold storage in NS or UW impairs endothelial-dependent coro nary relaxation in the isolated rat heart model.