苦皮藤素Ⅴ引起粘虫兴奋的作用机理初探

Study on the mechanism of action of celangulin Ⅴ

苦皮藤素 是从杀虫植物苦皮藤 (Celastrus angulatus Max)根皮提取物中分离得到的对昆虫有毒杀活性的一种新化合物。通过对该化合物引起粘虫产生类似神经毒剂兴奋性症状的机理研究 ,结果表明 ,苦皮藤素 对昆虫中枢神经系统兴奋性突触后电位(EPSP)和轴突动作电位 (AP)无显著影响 ;试虫经苦皮藤素 处理后 ,抽搐期和失水期体内乙酰胆碱酯酶 (ACh E)活性分别下降 33.9%和 39.6% ,谷氨酸 (Glu)含量分别升高 2 8.44%和 49.1 8% ,γ-氨基丁酸 (GABA)含量分别降低 42 .1 1 %和 44.47%。抽搐期体内谷氨酸脱羧酶活性降低了 8.67%。

This paper preliminarily reports the mechanism of generating excitation as neurous insecticides of Celangulin Ⅴ isolated from the root part of Celastrus angulatus Max,using electrophysiological and biochemical methods.The electrophysiological results show that Celangulin Ⅴ has no effects on the excitatory postsynaptic potential (EPSP) and the action potential of the nerve giant fiber axon from the cockroach CNS preparation.After the sixth instar larvae of Mythimna separata following oral administration with Celangulin Ⅴ,the activity of acetyl choline esterase (AChE) of excitatory and convulsionary larvae decreased by 33.9% and 39.6% respectively,compared with normal larvae;the glutamate (Glu) content raised by 28.44% and 49.18% and the content of γ aminobutiric acid (GABA) reduced by 42.11% and 44.47% .In the convulsionary larvae,the activity of glutamic decarboxylase decreased by 8.67% .