Organ preservation with EC, HTK, and UW, solution in orthotopic rat liver transplantation. Part II. Morphological study

The quality of organ preservation is of major importance in minimizing the incidence of primary graft nonfunction and organ rejection. For this study a new semiquantitative score was developed that grades morphologic tissue a lterations in the liver according to their frequency and severity. It was a pplied to assess commonly used perfusion solutions for their efficacy in pr eventing early and late tissue damage after rat liver transplantation. For transplantation the livers were stored in Euro-Collins (EC, group I; n = 11 ), histidine-tryptophan-alpha-ketoglutarate (HTK, group II; n = 11), or Uni versity of Wisconsin solution (UW, group III; n = 11). Rat liver transplant ation was performed with graft arterialization by the method of Engemann. B iopsies were taken for morphological examination and semiquantitative scori ng during the donor operation, after 4 h of cold storage, 1 h after reperfu sion, and 4 weeks postoperatively. An immunohistological bromodeoxyuridine (BrdU) assay was also performed on the day of dissection to assess the rate of hepatic proliferation. Semiquantitative morphological analysis gave wid ely differing results in all experimental groups after 4 h of ischemia. The re was less intracellular and interstitial edema, fatty degeneration, intra lobular necrosis, and hepatocellular proliferation in the HTK group than in the other groups. Neither after cold ischemia nor 1 h after reperfusion di d Kupffer-cell activation occur; this is known to play a major role in the development of ischemia and reperfusion injury. Furthermore, late changes s uch as bile-duct proliferation and vascular and sinusoidal alterations appe ared less frequently in this group. The hepatoprotective powers of HTK solu tion might therefore be due to decreased Kupffer-cell activation.