Effect of vitamin E, topical hypothermia and steroid on ischemic liver in rats

Major hepatic surgery often requires temporary occlusion of the porta hepatis in order to minimize intraoperative bleeding. Occlusion of porta hepatis induces hepatic ischemia and may cause liver damage. This study was conducted to evaluate the effects of vitamin E, topical hypothermia and administration of steroids on ischemic liver by assessing the hepatic levels of lipid peroxides and examining the ultrastructural change of mitochondria. One hundred and twenty male wistar rats were divided into four groups, each of 30. All rats underwent laparotomy and the liver ischemia experiment was conducted by clamping the porta hepatis for 15 minutes. Group A received no further treatment, group B received vitamin E (30IU/Kg/B.W) supplementation for one week before experiment, group C was topically cooled and group D received preocclusion intravenous methylprednisolone (2mg/Kg/B.W). Hepatic lipid peroxides, expressed as nmol MDA/g wet wt were assessed by spectrofluorometric methods, and were measured immediately before occlusion, 15 min after occlusion, and 15 min after reperfusion. The results showed that the concentration of lipid peroxides increased markedly after occlusion of porta hepatis in group A, which received no treatment in ischemic liver (8.76 +/- 3.19 vs. 10.49 +/- 3.35 MDA nmol/g wet wt, p < 0.05, paired t-test), while the concentrations of hepatic lipid peroxides were not found to increase in groups B, C or D. In the meantime, the ultrastructural study showed marked swelling of mitochondria in ischemic liver of group A rats only. This suggests that vitamin E supplementation, topical hypothermia and administration of steroids will inhibit the propagation of lipid, peroxidation and provide protective effects on liver parenchyma during ischemia.