Effect of perfusate albumin on organ viability and vascular responses in the in vitro dual-perfused rat liver

Inclusion of albumin in the perfusate has been previously shown to be detri mental to liver function, but its effect on hepatic vascular reactivity rem ains unknown. The aim of this study was to determine the effects of albumin on hepatic arterial vascular reactivity and liver viability in the isolate d dual-perfused rat liver. A total of 12 rat livers were perfused with Kreb s-Bulbring buffer without (Group I) and with (Group 2) addition of 1% bovin e serum albumin (BSA) through the hepatic artery and portal vein for up to 5 h. Hepatic arterial responses to acetylcholine and sodium nitroprusside w ere studied at 30-min intervals. Liver viability was assessed by bile Volum e production, release of aspartate serine aminotransferase (AST) and lactic acid dehydrogenase (LDH), and histological examination. Hepatic arterial r esponses to acetylcholine were significantly attenuated in Group 2. No sign ificant differences in sodium nitroprusside responses were noted. However, bile volume production in Group 2 was significantly decreased compared to G roup 1. Effluent AST and LDH release increased significantly in Group I but not in Group 2. Histological results showed that sinusoidal endothelial ce lls and hepatocytes were well preserved without significant deterioration i n either group, although there was a marked decrease in vasodilatation to a cetylcholine in Group 2. This data suggested that the presence of albumin i n the perfusate did not improve retention of smooth muscle reactivity and r educed endothelium-dependent vasodilatation and bile volume production duri ng perfusion. However, improved liver parenchymal cell function was observe d. (C) 2001 Elsevier Science Inc. All rights reserved.