缺血预处理对大鼠肝脏部分切除术后残留肝脏的保护作用及其机制的研究

目的　探讨缺血预处理 (ischemicpreconditioning ,IPC)对大鼠肝脏部分切除术后残留肝脏的保护作用及其机制。方法　 5 0只雄性SD大鼠随机均分为假手术 (Sham)、单纯热缺血 (warmis chemia ,WI)、IPC、IPC L arginine(NO供体 )和WI NAME(NO合成酶抑制剂 ) 5组。术前、术后 1、2、3d检测血清AST和ALT ,术前、IPC后、热缺血后 0 5、1、2、3h检测肝脏组织NO浓度。AST和ALT用自动生化分析仪检测 ,NO用硝酸还原法检测。结果　WI、IPC、IPC L arginine及WI NAME组术后AST和ALT均高于Sham组 (P <0 0 5或P <0 0 1) ,IPC和WI NAME组术后AST和ALT低于WI和IPC L arginine组 (P <0 0 5 )。WI、IPC、IPC L arginine及WI NAME组术后 0 5h肝脏组织NO浓度开始升高(P <0 0 5或P <0 0 1) ,IPC和WI NAME组术后肝脏组织NO浓度低于WI和IPC L arginine组 (P <0 0 5 )。结论　IPC对大鼠肝脏部分切除术后残留肝脏的缺血再灌注损伤有保护作用。IPC通过抑制大鼠热缺血再灌注肝脏产生NO ,减少NO所诱发的肝脏组织细胞的凋亡或坏死 ,保护肝脏功能。

Protective effect of ischemic preconditioning on residual liver after partial hepatectomy in rats and its mechanism

Objective To investigate the effect of ischemic preconditioning (IPC) on residual liver after partial hepatectomy and explore its mechanism. Methods Fifty male SD rats were equally divided into 5 groups that received sham operation, warm ischemia (WI), IPC, IPC L-arginine and WI NAME, respectively. The serum levels of AST and ALT were determined before and in 1,2 and 3 d after the operation. NO density in hepatic tissues was determined before operation, after IPC and 0.5, 1, 2 and 3 h after the operation by the method of nitrose reduction. Results After operation, the serum levels were significantly higher in the groups of WI, IPC, IPC L-arginine and WI NAME than in the sham-operated group (P<0.05 or 0.01). However, they were markedly lower in groups of IPC and WI-NAME than in groups of WI and IPC L-arginine (P<0.05). NO density began to increase 0.5 h after the operation in groups of WI, IPC, IPC L-arginine and WI NAME. The density was remarkably lower in groups of IPC and WI NAME than in groups of WI and IPC L-arginine (P<0.05). Conclusions IPC can protect rat's residual liver from warm ischemia-reperfusion injury after partial hepatectomy because it can inhibit NO generation in liver undergoing ischemia-reperfusion and reduce cell apoptosis and necrosis of the liver.