氟他胺和2—羟基氟他胺对大鼠原代培养肝细胞毒性及CYP1A2mRNA的影响

目的:比较氟他胺及其活性代谢产物2-羟基氟他胺对原代培养大鼠肝细胞毒性及对CYP1A2 mRNA的影响.方法:分离大鼠肝细胞,原代培养4h,台酚蓝拒染法检测肝细胞活力.氟他胺和2-羟基氟他胺在培养液中浓度分别为10、20和50mg/L.肝细胞毒性检测包括台酚蓝拒染法,乳酸脱氢酶(LDH)释放量,谷丙转氨酶(AST)和谷草转氨酶(ALT)释放百分比,谷胱甘肽(GSH)含量.同时采用Northern blot方法进一步研究两药对CYP1A2 mRNA的影响.结果:药物作用8h后,氟他胺三个剂量组和2-羟基氟他胺50mg/L组出现肝细胞损伤,表现为ALT和AST释放百分比增加,GSH含量下降.氟他胺三个剂量组使CYP1A2 mRNA水平分别升高2,5和7.5倍,而2-羟基氟他胺仅在50mg/L时使CYP1A2mRNA水平升高3.5倍.结论:氟他胺对原代培养大鼠肝细胞的毒性大于其活性代谢物2-羟基氟他胺,且明显增加CYP1A2 mRNA水平.

Cytotoxicity of flutamide and 2-hydroxyflutamide and their effects on CYP1A2 mRNA in primary rat hepatocytes

AIM: To compare the cytotoxicity of flutamide and its active metabolite 2-hydroxyflutamide and their effects on cytochrome P-450 1A2 mRNA in primary rat hepato-cytes. METHODS: After the isolation of hepatocytes and the primary incubation for 4 h, flutamide and 2-hydroxyflutamide were added respectively to the medium at the concentration of 10, 20, and 50 mg/L and incubated for 8 h. Cytotoxicity of hepatocytes was assessed by Trypan blue exclusion, lactate dehydrogenase (LDH) leakage, percentage of alanine aminotransferase (ALT) or aspartate aminotransferase (AST) release, and reduced glutathione (GSH). The effect of flutamide and 2-flutamide on the CYP1A2 mRNA level was further analyzed by Northern blot. RESULTS: After incubation for 8 h, cell viability was observed by Trypan blue exclusion. The increase of ALT and AST activity and the decrease of glutathione content were also noted at 10, 20, and 50 mg/L of flutamide and 50 mg/L of 2-hydroxyflutamide as compared with normal rat hepatocytes. Induction of CYP1A2 mRNA were 2-, 5-, and 7.5-fold at 10, 20, and 50 mg/L of flutamide and 3.5-fold at 50 mg/L of 2-hydroxyflutamide. CONCLUSION: Cytotoxicity of flutamide and its effect on CYP1A2 mRNA were stronger than those of its active metabolite 2-hydroxyflutamide in primary rat hepatocytes.