摘要
目的 研究除草剂氟乐灵对大鼠肝、肾微粒体酶的作用。方法 采用体内和体外方法 ,研究了氟乐灵对大鼠肝、肾微粒体酶影响以探讨其毒作用及可能机制。结果 ①连续灌胃 5天后氟乐灵 ( 5 0 0mg/kg)能诱导肝微粒体细胞色素P45 0和苯胺羟化酶 (AH )活性 (P <0 0 5 ) ,明显诱导细胞色素b5含量和NADPH 细胞色素C还原酶活性 (P <0 0 1) ,同时使肝重、肝微粒体蛋白含量显著增加。体外实验中 ,氟乐灵在高浓度 ( 2 5× 10 -4 mol/L)条件下可明显诱导肝细胞色素P45 0 (P <0 0 1)。对AH的酶动力学研究表明氟乐灵可增加AH的最大反应速度 (Vmax) ,对其米氏常数 (Km)无明显影响 ,可见氟乐灵对AH的诱导不是通过改变AH与底物的亲和力实现的 ,而可能与促进蛋白合成有关。②体内实验中氟乐灵可使肾微粒体NADH 细胞色素C还原酶活性显著增加 (P <0 0 5 ) ,而对肾细胞色素P45 0、b5以及NADPH 细胞色素C还原酶无明显影响。结论 氟乐灵可明显诱导大鼠肝微粒体混合功能氧化酶系。
Objective To study the influence of trifluralin on the microsomal enzymes of liver and kidney.Methods Vivo and vitro methods were used to explore the effects of trifluralin.Results First, after administration with trifluralin at 500 mg/kg body weight for 5 days, the rats liver weights were significantly increased compared with that of control. The contents of liver microsomal cytochrome P 450, b 5 and protein, the activities of AH and NADPH cytochrome C reductase were dramatically induced. The effect of trifluralin on kinetic property of AH was also studied. It was found that Km of AH remained almost as the same as that of control after treament with trifluralin. In vitro, liver cytochrome P 450 was dramatically induced by trifluralin at 2.5×10 -4 mol/L concentration, however, no obvious change was observed in cytochrome b 5. Sencond, after treatment with trifluralin, renal microsomal NADH cytochrome C reductase was markedly induced, while no significant changes was detected in the contents of cytochrome P 450, b 5, and NADPH cytochrome C reductase activity. Conclusion Trifluralin has certain induction effects on rats microsomal enzymes.
出处
《中国职业医学》
CAS
2000年第5期16-18,共3页
China Occupational Medicine
