羟基马桑毒素及其衍生物对粘虫体内GAD和GABA-T活性的影响

Effects of Tutin and Its Derivatives on GAD and GABA-T Activities of Pseudelatia separata

为了探明羟基马桑毒素及其衍生物(T1、T2、T3、T4)对粘虫神经系统的影响以及快速检测对比分析新合成的药物对试虫神经递质γ-氨基丁酸(GABA)相关酶谷氨酸脱羧酶(GAD)和γ-氨基丁酸转氨酶(GABA-T)活性的影响,通过胃毒和离体2种处理方式提取粗酶液并采用分光光度法对试虫酶活性进行测定。结果表明,经羟基马桑毒素及其衍生物处理后试虫的GAD酶活受到了抑制,而GABA-T活性被提高,这2种酶影响着试虫体内GABA的含量。离体测定的结果与胃毒处理后试虫体内酶活的变化相似,因此可以采用离体处理方法快速检测新药物对试虫的活性。

To understand the effects of tutin and its derivatives（T1,T2,T3,T4） on the nervous system of Pseudelatia separata and quickly determine the activities of glutamic acid decarboxylase（GAD） andγ-aminobutyric acid transaminase（GABA-T） treated by new synthesized compounds,the crude enzymes were extracted from 3rd instar larvae and the spectrophotometry was used to assay the activities of enzymes.One method of enzyme activity determination was to feed the larvae with toxins,and the other is to add toxins into enzyme directly.The results showed that GAD activities were inhibited by tutin and its derivatives,but the GABA-T activities were stimulated,both of them were impacted by the contents of GABA.The enzyme activities determined by two methods were similar,indicating that the method of activities determination of enzymes adding toxins directly could be used on the activities quick determination of new compounds.