Abstract：
Recent events have shown that organophosphorus nerve agents (OPNAs) are a serious threat. Cholinesterase inhibition by OPNAs results in acetylcholine accumulation, a cholinergic crisis leading to death if untreated. Efficacy assessment of new medical countermeasures against OPNAs relies on translational animal models. We developed a swine model of percutaneous VX intoxication and a simple plate reader-based enzymatic method to quantify plasmatic VX over time. Juvenile pigs anesthetized with sevoflurane were poisoned with a single supralethal (n = 5; 1200 μg/kg) or sublethal (n = 6; 320 μg/kg) percutaneous dose of VX. These intoxicated animals were compared to 7 control animals. Repeated blood sampling was performed up to 6 h post-intoxication. Blood cholinesterase activities were measured using the Ellman assay. Nanomolar plasma concentrations of VX were measured by exogenous butyrylcholinesterase added to an aliquot of plasma. As expected, we observed a steady increase in plasma concentration of VX over time concomitant to a decrease in blood cholinesterase activities for all intoxicated pigs. Despite the simplicity of the enzymatic method, the results obtained are in good agreement with those of the liquid chromatography-mass spectrometry method. This method is also applicable to other OPNAs such as novichoks with minor adaptations.
摘要：
最近的事件表明，有机磷神经毒剂（OPNAs）是一个严重的威胁。OPNA抑制胆碱酯酶导致乙酰胆碱积累，如果不治疗会导致死亡的胆碱能危机。针对OPNA的新医学对策的功效评估依赖于转化动物模型。我们开发了一种经皮VX中毒的猪模型和一种简单的基于平板读数器的酶促方法来随时间定量血浆VX。用七氟醚麻醉的幼猪被单次超致死（n=5;1200μg/kg）或亚致死（n=6;320μg/kg）经皮剂量的VX中毒。将这些中毒的动物与7只对照动物进行比较。重复采血直至中毒后6小时。使用Ellman测定法测量血液胆碱酯酶活性。通过将外源性丁酰胆碱酯酶添加到等分血浆中测量VX的纳摩尔血浆浓度。不出所料,我们观察到VX的血浆浓度随时间稳定增加,同时所有中毒猪的血胆碱酯酶活性降低.尽管酶法很简单，获得的结果与液相色谱-质谱法的结果非常吻合。此方法也适用于其他OPNA，例如具有较小改编的novichoks。
