细辛醚对粘虫幼虫的毒力及几种重要酶系的影响

采用点滴法测定了细辛醚对粘虫Mythimna separate Walker 5龄幼虫的触杀毒力，观察了细辛醚对粘虫的致毒症状，并测定了对不同中毒阶段其头部或中肠乙酰胆碱酯酶（AChE）和腺苷三磷酸酶(ATPase)离体活性以及乙酰胆碱（ACh）含量的影响。结果表明：细辛醚对粘虫5龄幼虫12 h的触杀LD₅₀值为106.93 μg/头；中毒粘虫依次表现出兴奋、痉挛、麻痹和死亡等症状，类似于神经毒剂的致毒症状，但试虫从中毒到死亡历期较长，且中毒试虫肠内有气泡产生，此现象异于典型的神经毒剂；对Na+，K+-ATPase有较强的抑制作用，在兴奋期、痉挛期和麻痹期，酶抑制率分别为33.29%、44.45%和23.98%；对AChE活力在不同阶段的抑制率分别是21.64%、29.75%和35.22%；ACh含量有所增加。

Toxicity of sarisan against Mythimna separata Walker and its effects on AChE and ATPases

The contact toxicity of sarisan against 5th instar larvae of Mythimna separate Walker was tested under the laboratory conditions with the method of topical application, their toxicity symptoms were observed, and its effects on the in vitro activities of AChE and ATPase and the content of ACh in heads or midguts of the larvae in different stages of toxicity were assayed. The results showed that the contact toxicity LD₅₀ value of sarisan against the 5th instar larvae of M. separate in 12 h post treatment was 106.93 μg/larva. In vivo toxicity symptoms were characterized by a definite sequence of events, starting with excitation, convulsion, paralysis, and death. Hollow duodenum was found in M. separata.AChE and Na+， K+-ATPase in M. separate larvae were strongly inhibited by sarisan, and a higher ACh content was caused  by sarisan. During excitation, convulsion and paralysis of treated larvae, the inhibition rates of AChE were 21.64%, 29.75% and 35.22%, respectively, while the inhibition rates of Na+，K+-ATPase were 33.29%, 44.45% and 23.98%, respectively.