Establishment of mice model of partial hepatic ischemia reperfusion injury

Objective To establish mice model of partial hepatic ischemia reperfusion (IR) injury and investigate the variation trend of injury evaluation indexes.
Methods Ninetysix male C57BL/6 mice (aged 7-8 weeks) were divided into 4 groups according to the ischemia time to construct hepatic IR model: sham operation group (24 mice), IR 30 minutes group (24 mice), IR 60 minutes group (24 mice) and IR 90 minutes group (24 mice). The mice in each group were sacrificed at hour 6, 12, 24, 48 after IR. The injury of the hepatic tissues in the 4 groups was analyzed based on detecting the levels of alanine transaminase (ALT), aspartate transaminase (AST), tumor necrosis factorα (TNFα), interleukin 6 (IL6), macrophage inflammatory protein 2 (MIP2), the histopathological grading and apoptosis index. All data were analyzed using the t test.
Results Eight mice died, and the success rate of model construction was 91.7%(88/96). The levels of ALT in the sham operation group, IR 30, 60 and 90 minutes groups were (35±24)U/L, (1703±442)U/L, (5133±681)U/L and (8233±808)U/L, respectively. The levels of ALT in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=6.54, 12.97, 17.56, P<0.05). The levels of AST in the sham operation group, IR 30, 60 and 90 minutes groups were (87±28)U/L, (2667±451)U/L, (6333±778)U/L, (9967±1168)U/L, respectively. The levels of AST in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=9.89, 13.89, 14.65, P<0.05). The levels of TNFα in the sham operation group, IR 30, 60 and 90 minutes groups were (14±5)μg/L,(83±14)μg/L, (133±17)μg/L, (202±21)μg/L,respectively. The levels of TNFα in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=7.78, 11.82, 15.34, P<0.05). The levels of IL6 in the sham operation group, IR 30, 60 and 90 minutes groups were (32±9)μg/L, (493±168)μg/L, (844±166)μg/L, (1345±198)μg/L, respectively. The levels of IL6 in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=4.74, 8.46, 11.48, P<0.05). The levels of MIP2 in the sham operation group, IR 30, 60 and 90 minutes groups were (37±11)μg/L, (102±35)μg/L, (177±32)μg/L, (279±50)μg/L, respectively. The levels of MIP2 in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=3.05, 7.28, 8.19, P<0.05). The apoptotic indexes in the sham operation group, IR 30, 60 and 90 minutes groups were 1.7%±2.1%, 22.7%±8.6%, 54.3%±11.2% and 76.3%±14.8%, respectively. The levels of apoptotic indexes in the IR 30, 60 and 90 minutes groups were significantly higher than the sham operation group (t=4.10, 8.04, 8.63, P<0.05). Under the same ischemia time, the changes of ALT, AST, TNFα, IL6 and apoptosis index were presented as the parabolic style as the increase of the reperfusion time.
Conclusions The mice model of hepatic IR injury could reflect the injured condition of the hepatic tissue of mice. Along with the time extension of ischemia, the severity of hepatic IR aggravated gradually. With the time extension of reperfusion, the levels of ALT, AST, TNFα, IL6, MIP2, histopathological grading and apoptosis index change in a parabolic trend.