乐果亚急性暴露对大鼠胆碱酯酶浓度及细胞色素P450亚型表达量的影响

对6周龄雄性Wistar大鼠5次灌胃给予20%LD_(50)的乐果,观察给药后大鼠的毒性反应,每日测定实验鼠采食量、饮水量和体重。最后一次给药后第24 h,采用丁酰硫代胆碱法测定大鼠红细胞、血清和脑组织中的胆碱酯酶浓度,并采用定量RT-PCR法检测大鼠肝中细胞色素P450基因8个亚型的表达量。结果表明,大鼠用药后不同时间内出现了有机磷药物中毒的典型症状,其采食量、饮水量和体重明显下降,红细胞、血清和脑组织中胆碱酯酶浓度均明显低于对照组,肝细胞色素P450的8个亚型中CYP2B1/2的表达量明显高于对照组。

Effects of subacute dimethoate administration on acetylcholinesterase and subtype of hepatic cytochrome P450 of rats

20% of LD_(50)of dimethoate was administrated orally five times to male Wistar rats of 6 weeks old.Toxicological reaction was observed after administration.The quantity of foraging and drinking and body weight were measured daily.The rats were anesthetized with ether and samples of red blood cell, blood serum,liver and brain were prepared after collecting blood from main artery of abdomen in 24 hours after last administration.The activity of acetylcholinesterase of red blood cell,blood serum and brain was analysed by the method of butyrythiocholin.The expression level of subtype of hepatic cytochrome P450 was assessed by RT PCR.The results indicated that the quantity of foraging and drinking and body weight of rats were decreased at different times after administration.Typical toxicological symptom appeared in the administrated rats.Acetylcholinesterase of red blood cell,blood serum and brain of rats in experimen- tal group were significantly lower than that of the control group.Hepatic CYP2B1/2 of rats in the experi- mental group were significantly higher than that of rats in the control group.