组织蛋白酶B在小鼠暴发性肝衰竭肝组织中的表达

目的研究组织蛋白酶B在暴发性肝衰竭小鼠肝组织中的表达。方法雄性昆明种小鼠腹腔同时注射脂多糖和D-氨基半乳糖,动态观察给药后2、4、6、8 h肝脏病理改变;以TUNEL法检测肝细胞凋亡;应用免疫组化和RT-PCR检测肝组织中组织蛋白酶B的表达。结果肝组织病理：给药后4 h出现凋亡细胞,6 h大量肝细胞凋亡,8 h以肝细胞坏死为主;TUNEL：给药后凋亡指数逐渐升高,6 h达到高峰,8 h有所降低;免疫组化：组织蛋白酶B表达2 h无明显变化（P〉0.05）,4 h逐渐增加,8 h达到高峰（P〈0.05）;RT-PCR：2 h组织蛋白酶B mRNA的表达量无明显变化（P〉0.05）,4 h表达略有升高,6 h表达最高,8 h表达有所降低（P〈0.05）。结论组织蛋白酶B在小鼠暴发性肝衰竭肝组织中表达明显增加,提示其可能通过促进肝细胞的凋亡而参与了暴发性肝衰竭的发病。

Expression of cathepsin B in liver tissue of fulminant hepatic failure in mice

Objective To study the expression of cathepsin B in liver tissue of fulminant hepatic failure in mice.Methods Galactosamine（D-Gal） and lipopolysaccharide（Lps） were injected into the abdominal cavity of the mice to induce fulminant hepatic failure.Liver pathological changes were determined with HE at 2,4,6 and 8 h after Lps/D-Gal injection.Hepatocyte apoptosis was examined by TUNEL method.The expression of cathepsin B in liver tissue was investigated by immunohistochemical staining and RT-PCR.Results Slight hepatocyte apoptosis at 4 hours after drug injection were observed;there were massive typical hepatocyte apoptosis at 6 hours after drug administration;after 8 hours injection,hepatocyte necrosis were widespread.Massive hepatocyte apoptosis occurred and the number of apoptosis cells were obviously increased as time went on;the apoptosis index （AI） was peaked at 6 hours after injection of Lps/D-Gal;at 8 hours after drug injection,it was lower than that of 6 hours.Strongly positive immunoreactivity for active cathepsin B was detected in the mice injected with Lps/D-Gal.The expression of cathepsin B did not significantly increase at 2 hours after drug injection（P〉0.05）,however,more expression of cathepsin B were gradually found at 4 hours and reached a climax at 8 hours after drug injection（P〈0.05）.The expression of cathepsin B mRNA was significantly increased after treatment of Lps/D-Gal.The expression of cathepsin B mRNA did not significantly increase at 2 hours after drug injection（P〉0.05）,more expression of cathepsin B mRNA was found at 4 hours after drug injection,the expression of cathepsin B mRNA was peaked at 6 hours and reduced at 8 hours after drug injection（P〈0.05）.Conclusion The expression of cathepsin B significantly increase in liver tissue of fulminant hepatic failure in mice.Cathepsin B has an essential role in the pathogenesis of fulminant hepatic failure.