大鼠杀虫双染毒后全血胆碱酯酶活力的变化

目的 探讨沙蚕毒系农药杀虫双对胆碱酯酶（ChE）活力是否有抑制及抑制的程度。方法 Wistar大鼠分为4组，分别以杀虫双或甲胺磷按1／16、1／8、1／4、1／2LD50剂量经口染毒，于染毒前及染毒后1／2、1、2、4、24h取大鼠尾尖血，以改良Ellman法测定ChE活力。结果 杀虫双1／16LD50剂量组染毒大鼠血ChE活力未受影响；随染毒剂量的加大，ChE活力逐步下降，1／2LD50剂量组大鼠血ChE活力抑制率为正常组的35.9%，差异有显著性（P＜0.01)。甲胺磷1／16LD60染毒剂量组大鼠血ChE活力抑制率为正常对照组的42.4%；随染毒剂量的加大，大鼠血ChE的活力进一步下降，1／2LD50剂量组大鼠血ChE活力抑制率达正常对照组的52.9%。各剂量杀虫双染毒组的ChE活力均高于对应的甲胺磷染毒组，差异有显著性（P＜0.01)。结论 大鼠经口杀虫双染毒后，在较高染毒剂量下可以抑制ChE活力，但抑制程度明显弱于甲胺磷。

The activity of blood cholinesterase in rats exposed to dimehypo

Objective To determine whether and to what degree the activity of cholinesterase(ChE) is inhibited by dimehypo at different doses of dimehypo scientific name:2 dimethylamine 1,3 bi(sodium hyposulfit)]. Method Rats were dosed with dimehypo or methamidophos orally,and were randomly divided into four subgroups according to the pesticide doses,which were 1/16,1/8,1/4 and 1/2 of LD 50 respectively(the LD 50 of dimehypo and methamidophos is 342 mg/kg and 20 mg/kg respectidely).The activity of ChE in blood was determined before and 30 min,1,2,4 and 24 h after exposure.The modified Ellman Method was employed to measure the activity of ChE. Result 1/16 LD 50 dose of dimehypo did not affect the activity of ChE.When the dose increased,the activity of ChE decreased accordingly.1/2 LD 50 dose of dimehypo inhibited the activity of ChE by 35.9% compared with that of control group( P <0.01).In rats dosed with methamidophos,even 1/16 LD 50 dose inhibited the activity of ChE by 42.4% compared with that of control group.When the dose of methamidophos increased,the activity of ChE decreased accordingly.1/2 LD 50 dose of methamidophos inhibited the activity of ChE by 52.9%.The activity of ChE in the rats dosed with dimehypo at various doses was significantly lower than that in the rats dosed with corresponding doses of methamidophos( P <0.01). Conclusion Higher doses of dimehypo may inhibit the activity of ChE.However,as compared with methamidophos,dimehypo is a weaker inhibitor of ChE.