Cholinesterase Inhibition as Target of Pesticide Residue

描述(由申请者提供)：在这个项目中，研究是为了分析 作为毒物的有机磷杀虫剂，接触有机磷的后果，在身体负担和靶标乙酰胆碱酯酶(AChE)抑制方面的后果，以及与有机磷靶标相关的个体敏感性的差异。将探索使用AChE目标本身进行荧光检测，作为开发遥感和便携式检测设备的一种手段。有机磷在体内的分布将通过质谱仪进行分析，以评估AChE活性中心的组织分布和结合。后一种方法使我们能够检测到抑制的AChE、抑制的和老化的AChE以及自发或再激活的AChE。因此，活性中心丝氨酸上反应的完整动力学轮廓是可能的。由于马拉硫磷在全球和当地的广泛使用，初步研究将涉及这种有机磷，它必须转化为马拉松才能成为一种活性和有毒的制剂。将使用P450活性增强的动物来研究转化率，P450活性可以控制前毒物向胆碱酯酶反应实体的转化。这些关于杀虫剂暴露的研究将通过检测乙酰胆碱酯酶基因及其选择性剪接外显子和基因调节区已被修改的转基因菌株来支持。修改后的基因使我们能够在选定的组织和离散的细胞位置表达AChE，从而能够分析 完好无损的动物。最后，研究人员采用了药物基因组学方法来检测单个多核苷酸多态，并反过来通过单倍型来分析对 胆碱酯酶抑制剂。以往对乙酰胆碱酯酶分子和编码该酶的单基因的研究使研究者在分析杀虫剂相互作用的目标分子和确定个体易感性的遗传关系方面处于有利地位。

DESCRIPTION (provided by applicant): In this project, studies are proposed to analyze organophosphate insecticides as toxicants, the consequences of organophosphate exposure, in terms of body burden and inhibition of the target acetylcholinesterase (AChE), and differences in individual susceptibility related to organophosphate target. Fluorescence detection using the AChE target itself will be explored as a means for developing remote sensing and portable detection devices. The disposition of organophosphates in the body will be analyzed by mass spectrometry to assess tissue distribution and conjugation at the active center of AChE. The latter approach enables us to detect inhibited AChE, inhibited and aged AChE and AChE that is spontaneously or oxime reactivated. Hence, a complete kinetic profile of reactions at the active center serine is possible. Because of malathion's prevalent use world-wide and locally, initial studies will involve this organophosphate which must be converted to malaoxon to become an active and toxic agent. Rates of conversion will be studied using animals with enhanced P450 activity which control the conversion of protoxicant to cholinesterase reactive entity. These studies of insecticide exposure will be buttressed by examining transgenic strains where the acetylcholinesterase gene, its alternatively spliced exons and regulatory regions of the gene have been modified. The modified genes enable us to express AChE in select tissues and in discrete cellular locations thereby allowing an analysis of the cellular basis of toxicity in the intact animal. Finally, the investigators have adopted a pharmacogenomic approach to detect single polynucleotide polymorphisms and, in turn, haplotypes to analyze differential sensitivity to cholinesterase inhibitors. Previous studies characterizing the AChE molecule and the single gene encoding the enzyme place the investigators in a strong position to analyze the target molecule of insecticide interaction and determine genetic relationships in individual susceptibility.