目的研究氯氰菊酯和残杀威亚致死剂量处理后致倦库蚊羧酸酯酶活性的变化规律。方法采用紫外可见分光光度计活体测定酶的活性。结果处理24h,抗性种群致倦库蚊羧酸酯酶比活力是敏感品系的1.19倍;敏感品系处理48h后,处理组均表现出显著的抑制作用,且与24h相比,对照组、残杀威LC20和LC40处理组、氯氰菊酯LC20和LC40处理组的比活力分别下降24.71%、38.42%、97.42%、90.77%和95.76%,处理组比活力下降率均比对照组高。抗性种群处理48h后,除残杀威LC20处理组与对照组无统计学意义外,其他3个处理组均有统计学意义,残杀威LC40处理组比活力为11.6254nmol(/mgpro·min),表现为显著抑制作用,氯氰菊酯LC20和LC40处理组比活力分别为55.8868和54.5530nmol/(mgpro·min),与对照组相比表现出显著的诱导作用,且2个浓度处理组间差异无统计学意义。比活力与24h相比,除氯氰菊酯LC20处理组比活力增加23.89%外,对照组、残杀威LC20和LC40处理组、氯氰菊酯LC40处理组的比活力分别下降60.71%、59.14%、23.68%和47.87%,处理组比活力下降率均比对照组低。结论经氯氰菊酯和残杀威亚致死剂量在不同时间处理的敏感和抗性致倦库蚊羧酸酯酶比活力影响是不同的,表明不同药剂对同种昆虫羧酸酯酶的抑制作用不同,同一种药剂对不同种群的抑制作用也不相同。 Objective To study the changes of carboxylesterase activity of Culex pipiens quinquefasciatus after exposure to cypermethrin and lethal lethal dose. Methods The activity of the enzyme was determined by ultraviolet spectrophotometer. The results showed that the specific activity of carboxylesterase of Culex pipiens quinquefasciatus was 1.19 times higher than that of the susceptible strain after 24 h of treatment. After 48 h of treatment with the sensitive strain, the treatment group showed significant inhibitory effect. Compared with the control group, The specific activities of the LC20 and LC40 treatment groups, the cypermethrin LC20 and LC40 treatment groups decreased by 24.71%, 38.42%, 97.42%, 90.77% and 95.76%, respectively. The specific activity of the treatment groups was higher than that of the control group. After 48 h of treatment, the other three treatment groups were statistically significant except for LC20-treated group and control group, and the specific activity of propafen LC40-treated group was 11.6254 nmol (/ mgpro · min) The results showed that the specific activities of cypermethrin in LC20 and LC40 groups were 55.8868 and 54.5530nmol / (mgpro · min), respectively, which showed significant induction compared with the control group, and there was no significant difference between the two concentration groups significance. Compared with 24h, the specific activities of LC40 and cypermethrin LC40 in control group, LC20 and LC40 treatment groups were decreased by 60.71%, 59.14%, 23.68% and 47.87%, respectively, except that the activity of cypermethrin LC20 treatment group increased by 23.89% , The specific activity of treatment group than the control group. Conclusion The specific activities of carboxylesterase of Culex pipiens quinquefasciatus treated with cypermethrin and lethal lethal dose were different at different times, indicating that the inhibitory effects of different agents on carboxylesterase of the same species were different Different agents have different inhibitory effects on different populations.