摘要
以二化螟为材料研究了杀虫单、甲胺磷和顺丁烯二酸二乙酯 (DEM)对谷胱甘肽转移酶 (GSTs)的抑制作用。离体抑制试验结果表明 ,杀虫单和DEM都对二化螟GSTs活性有强烈的抑制作用 ,在实验设置的反应体系中 ,2 5mmol·L-1杀虫单和DEM与酶液保温 2min后 ,对GSTs的抑制率达到 70 %以上 ;6min后 ,达到 90 %以上。杀虫单和DEM的抑制中浓度 (IC50 )分别是 1 33和 1 71mmol·L-1,而甲胺磷没有抑制作用。活体实验结果显示 ,用 0 1mol·L-1杀虫单、甲胺磷和DEM 0 0 5 μL分别处理二化螟 4龄幼虫 48h后 ,杀虫单和DEM对GSTs活性的抑制率分别达 10 3%和 14 5 % ,甲胺磷则表现出 8 6 %的诱导作用。酶动力学实验显示 ,杀虫单和DEM都是GSTs的可逆性抑制剂 ,这种抑制作用不是竞争性的。由此表明 ,杀虫单是GSTs的强抑制剂 ,这在杀虫单的毒杀机制中具有重要的意义。
The inhibition of glutathione S transferase(GSTs)in rice stem borer by monosultap,methamidophos and DEM was studied.The experiment,in vitro,revealed that both monosultap and DEM showed strong inhibition to GSTs.In 2 minutes,culture with 2 5 mmol·L -1 monosultap or DEM,the enzyme lost more than 70% activity.And in 6 minutes,more than 90% enzyme was inhibited.The IC 50 was 1 33 and 1 71 mmol·L -1 for monosultap and DEM,respectively.Methamidophos,however,showed little inhibition against GSTs.The experiment,in vivo,was performed 48 h after the 4 th instar larvae were treated with inhibitors.The results indicated that monosultap and DEM displayed 10 3% and 14 5% inhibition against GSTs,respectively,while 8 6% more activity was induced by methamidophos.The dynamics of enzyme catalyzing revealed that monosultap and DEM were reversible inhibitor,and the inhibition reaction was not competitive.The study concluded that monosultap is a strong inhibitor against GSTs,and this may be significantly important in toxicology of this insecticide.
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2001年第3期27-30,共4页
Journal of Nanjing Agricultural University
基金
国家基础研究"973"项目 (J2 0 0 0 16 2 0 7)
国家自然科学基金 (30 0 70 5 0 2 )
