Research Article
Ischemia Effect on Lean and Steatotic Liver in Rats: Evaluating Levels of Lactic Acid and Transaminases
Konstantinos KostoulasIntroduction: Major hepatic surgery includes techniques of controlled ischemia and reperfusion in order to control bleeding and minimize blood loss. Fatty liver disease is considered to be an independent prognostic factor in major hepatic surgery, with negative impact on the outcome of patients. The aim of our experimental study was to evaluate the variance of concentration levels of Lactic Acid (LA) in liver tissue, as well as serum Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) levels, after the effect of different periods of liver ischemia followed by reperfusion in rats with lean and in rats with steatotic liver. Materials and methods: Eighty male Wistar rats aged 12-14 weeks were included. Forty of them were fed a regular laboratory diet, while the other forty were specially fed (choline-free diet) for 12-14 weeks in order to develop severe liver steatosis. Each of the groups was further divided into 4 subgroups: control group (sham-operated), 15, 30 and 45 minutes of surgically induced ischemia. After completion of the ischemic manipulation partial hepatectomy was performed for non-ischemic lobes and reperfusion for ischemic liver lobes. Rats were euthanized and liver tissue was used to measure LA. Blood samples were obtained and used to measure AST and ALT. Results: LA and aminotransferases levels were higher in steatotic rats than in lean rats in every subgroup (including control groups). Values of LA, AST and ALT increased within the same group (steatotic or lean rats) as the ischemia was prolonged (among different subgroups). Conclusion: Steatotic rats undergoing ischemia appear to elevate LA, AST and ALT significantly more than lean rats under the same manipulation, related to the time of exposure to hepatic ischemia. This suggests that the steatotic liver is less tolerant to ischemia than the lean one.