缺血预适应对大鼠肢体缺血再灌注后肝损伤的影响

The Effect of the Ischemic Preconditioning on Apoptosis of Liver Cells after Limb Ischemia Reperfusion in Rats

目的:观察缺血预适应(IPC)对大鼠肢体缺血再灌注(LIR)后肝脏损伤和细胞凋亡的影响,以进一步探讨IPC对肢体缺血再灌注后肝脏功能的保护作用。方法:将实验用雄性Wistar大鼠18只,随机分为对照组、缺血再灌注(IR)组和缺血预适应加再灌注(IPC+IR)组,每组6只。测定各组动物血浆中丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、透明质酸(HA)和乳酸脱氢酶(LDH);检测肝组织细胞的DNA双链百分率;利用原位脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL法)检测各组肝细胞凋亡情况;采用免疫组织化学方法检测各组动物肝组织Bcl-2和Bax比值及Caspase-3。结果:大鼠LIR后血浆中ALT、AST、HA、LDH含量均明显增加;LIR后肝组织细胞DNA双链百分率降低,凋亡细胞百分率增高。Bcl-2/Bax蛋白比值减小,Caspase-3蛋白表达明显增强。IPC+IR组上述各指标较IR组改善,但与对照组比较差异仍有统计学意义(P<0.05或P<0.01)。结论:肢体缺血再灌注可以导致肝脏的损伤,缺血预适应可以减轻损伤的发生,其保护效应可能与其抑制肝细胞凋亡有关。

Objective： To observe the effect of ischemic preconditioning （IPC） on hepatic injury and apoptosis of liver cells after limb ischemia-reperfusion, and to investigate the protective effect of IPC on the injury of liver function after limb ischemia-repeffusion. Methods： Eighteen experimental androgensis rats were randomly divided into three groups which included control group, ischemia-repeffusion （IR） group and ischemic preconditioning （IPC） group with 6 in each group. The contents of glutamic-pyruvic transaminase （ALT）, glutamic-oxaloacetic transaminase （AST）, hyaluronic acid （HA）, and lactate dehydrogenase （LDH） in plasma were measured in different groups. The percentage of DNA chain of liver tissue cells was measured. The apoptosis was detected by TdT-mediated Dutp nick end labeling （TUNEL）. The immunohistochemical method was used to detect the expression of Bcl-2, Bax and Caspase-3 in liver. Results： The contents of ALT, AST, HA, and LDH in plasma increased after limb ischemia reperfusion. Ratio of DNA chain decreased in liver tissue cells, and the percentage of apoptosis cell was significantly higher in IR group. The ratio of Bcl-2/Bax was lower, and the expression of Caspase-3 was significantly higher in IR group. The index of IPC＋IR group improved compared with that of IR group, but there was a statistical significance compared with control group （P 〈 0.05 or P 〈 0.01）.The abnormal phenomena could be reversed by IPC. Conclusion： Limb ischemia-repeffusion can cause liver injury, and IPC can alleviate the damage by reducing the occurrence of apoptosis of liver cells.