PROTECTION BY CAROLINA RINSE SOLUTION, ACIDOTIC PH, AND GLYCINE AGAINST LETHAL REPERFUSION INJURY TO SINUSOIDAL ENDOTHELIAL-CELLS OF RAT LIVERS STORED FOR TRANSPLANTATION

The critical injury causing graft failure after prolonged liver storag e involves reperfusion-induced killing of sinusoidal endothelial cells and activation of Kupffer cells. Treatment of stored livers with Caro lina rinse solution (CRS) prevents endothelial cell killing, reduces K upffer cell activation, and improves graft survival. Accordingly, our aim was to evaluate the components of CRS and other agents for protect ion against reperfusion injury to rat livers stored 24 hr in Universit y of Wisconsin solution. CRS virtually abolished endothelial cell kill ing, prevented denudation of the sinusoidal lining, and decreased stru ctural changes in Kupffer cells indicative of activation. The only com ponent of CRS preventing endothelial cell killing was acidic pH of 6.5 . However, when pH was subsequently increased to 7.4, antioxidants (al lopurinol, deferoxamine mesylate, and glutathione), vasodilators (aden osine and nicardipine), and possibly energy substrates (fructose, gluc ose, and insulin) partially blocked pH-dependent cell killing (pH para dox). Na+/H+ exchange inhibition, protease inhibition, and Ca2+-free b uffer did not decrease reperfusion injury, but the amino acid glycine protected strongly. Strychnine, which binds to glycine receptors in th e central nervous system, protected equally well. Protection by glycin e and CRS was synergistic, virtually eliminating cell killing after 48 hr of storage. Unlike CRS and some of its components (adenosine and C a2+ channel blocker), glycine did not block tumor necrosis factor-alph a release by cultured rat Kupffer cells, although gabexate mesylate, a protease inhibitor, strongly blocked tumor necrosis factor-alpha rele ase. In conclusion, the combination of CRS and glycine enhanced protec tion against reperfusion injury to stored livers and may prove benefic ial in improving graft function and survival after liver transplantati on.