以碘化硫代乙酰胆碱为底物,二硫代二硝基苯甲酸为显色剂,采用分光光度法测定了21种有机磷农药对乙酰胆碱酯酶(AChE)的半抑制浓度(IC50).运用多元线性回归分析以及参数间的自相关分析建立有机磷农药对AChE抑制作用的QSAR模型.模型分析表明,有机磷农药对AChE的抑制作用主要受特定方向上的原子极化率及原子的电拓扑状态的影响,是多因素综合作用的结果.模型可解释高达78%的数据变异和显著的预测能力(q^2=0.653),表明有机磷农药对AChE的抑制作用可借助结构活性关系模型进行预测与评价.
The half-inhibitory concentration (IC50) of 21 kinds of organophosphorous pesticides (OPs) on acetylcohnesterase (ACHE) was determined, adopting spectrophotometry, acetylthiocholine iodide as substrate and 5,5'-dithiobis-2-dinitrobenzoic acid (DTNB) as chromogenic reagent. The QSAR model of inhibition of OPs on AChE was established using multivariate linear regression analysis and the inter correlation analysis of parameters. This model analysis showed that the inhibition action of OPs on AChE was influenced mainly by the polarizabilities and electrotopological states of atoms in specific directions, resulted from synthetically action of multiple factors. The model could explain the data variation reaching 78% high, and marked prediction capacity (q^2=0.653), indicating that the inhibition of OPs on AChE could be predicted and evaluated in aid of the relation model of the structure.