有机磷农药对神经毒性酯酶活性抑制作用与其分配系数关系的研究  

Correlation between inhibition of NTE activity by organophosphorus insecticide and their partition coefficient

作　　者：田雨[1] 冷欣夫[1] 陈志强[1] 

机构地区：[1]中国科学院动物研究所

出　　处：《农药》1996年第11期6-8,共3页Agrochemicals

基　　金：国家自然科学基金

摘　　要：本文以白色成年莱亨母鸡为材料，进行了不同类型的有机磷农药以ＬＤ５０剂量处理鸡４８小时后取其脑组织匀浆液作酶源，测定其ＮＴＥ活性。在反应体系中分别加入对氧磷及对氧磷与氟丙胺磷混合液，以差异抑制法测定出反应终产物在５１０纳米处的ＯＤ值，以每分钟毫克蛋白所分解底物戊酸苯酯生成产物苯酚的量表示ＮＴＥ的活性。用反相液相色谱法测得标样化合物的保留时间（ｌｏｇＴＲ）与其正辛醇／水的分配系数（ｌｏｇＰ）呈线性关系。因而预测了２２种有机磷化合物的分配系数。发现某些有机磷化合物的分配系数大，其对ＮＴＥ活性的抑制作用也较强，但无明显的线性关系。This paper dealing with the activity of Neuropathy Target Enzyme (NTE) was inhibition by different type of organophosphorus insecticides (OPS). Adult white Leghorn hens (Gallus gallus domestics) were treated with a single oral LD50 dose of each OPS and housed one per cage in a temperature controlled room (about 20℃) with 12 hrs. light-dark cycles, and maintained on diet and tap water until sacrificed at 48 hrs. for use in the experiment.NTE was assayed in whole-brain homogenates from two hens . each brain was rapidly removed, placed into a baker of icecold buffer, stripped of meanings and superficial blood vessels,blotted and weighed, each brain was transferred to fresh ice-cold bufferand homogenated. An aliquot of each homogenate was diluted in buffer to give a final tissue concentration of 4.0mg/ml . 0.5 ml of buffer(blank)or diluted homogenate were added into a tube containing either 0.25 ml paraoxon (400μm in buffer) and 0.25 ml buffer or 0.25 ml paraoxon (400μm) and 0.25 ml mipafox (200μm) . The tubes were incubated in water both at 37℃. After 20 min. of incubation with inhibitors, 1.0ml of a dispersion of substrate(5.3mm phenyl valerat-0 . 063% (v/v) TritonX-100 in water)was added to each tube and incubated in a water bath at 37℃ for exactly 15 min. The reaction was terminated by adding the stopping solution (SDS) . 1. 0 ml of potassium ferrieyamide solution(4.0 mg/ml)was added. The developed color was stable for at least 1 hr. and measured at 510nm. The activity of NTE was estimated by the phenol standard curve on the difference of optical density between the sample incubated with paraoxon and sample with paraoxon plus mipatox.Reversed-phase HPLC has been applied to estimate the noctanol/water partition coefficient(logP)of 22 OPS. Based on the relationship between the inhibition of NTE activity by organophosphorus compounds and their logP, it seemed to be that the higher partition coefficient of OPS the stronger inhibition of NTE activity, but there is no closely position correlation.

关 键 词：有机磷农药 分配系数 神经毒性 酯酶活性 活性 

分 类 号：TQ450.2[化学工程—农药化工] TQ453.22