有机磷农药接触工人酯酶活力特征及基因多态对酶活力的影响

目的 研究接触有机磷农药对丁酰胆碱酯酶（BchE）、羧酸酯酶（CarbE）、对氧磷酶（PonE）和乙酰胆碱酯酶（AChE）活力的影响,并探讨酯酶基因多态性对长期接触有机磷农药工人酯酶活力的影响.方法 241名长期接触有机磷农药的生产工人为直接接触组,151名农药厂后勤人员为间接接触组,160名无有机磷农药接触的外厂工人为对照组.检测各组4种酯酶活力;用ABI 7900基因序列检测系统和基因芯片技术确定PON192、PON55和BchE基因型.结果对照组CarbE、BchE和PonE活力无年龄、性别差异.直接接触组、间接接触组的CarbE和BchE活力均明显低于对照组;直接接触组PonE活力明显低于对照组;直接接触组AChE活力明显低于间接接触组,差异均有统计学意义（P＜0.01）.直接接触组BchE基因型（UU、UK、KK）频率分别为74.3%、24.1%和1.6%;等位基因频率BCHE＊U=0.863、BCHE＊K=0.137.PON192基因型（AA,AB,BB）频率分别为15.0%、45.5%和39.5%;等位基因频率PON＊A=0.378、PON＊B=0.622.PON55基因型（MM、LM、LL）频率分别为96.2%、3.8%和0%;等位基因频率PON＊M=0.981、PON＊L=0.019.PON192和PON55不同基因型PonE活力差异有统计学意义（P＜0.01和P＜0.05）.结论 长期接触有机磷农药在不同程度上抑制4种酯酶的活力,PON192和PON55基因多态性影响有机磷接触工人PonE活力.

Activity of esterases and effect of genetic polymorphism in workers exposed to organophosphorus pesticides

OBJECTIVE: To study the activity of esterases, including butyrylcholinesterase (BchE), carboxylesterase (CarbE), paraoxonase (PonE) and acetylcholinesterase (AChE), and to explore the effect of genetic polymorphism on the activity of esterase for workers exposed to organophosphorus pesticides (OPs). METHODS: Two hundred and forty-one long term OPs directly exposed workers and 151 indirectly exposed workers in the same factory were taken as study group. One hundred and sixty unexposed persons were taken as control group. The activity of serum enzymes was measured and the polymorphic distribution was detected using 7900 genotype detecting system and CMOS Chip technique. The effect of long-term exposure to organophosphorus pesticides was analyzed. RESULTS: The activities of BchE, CarbE and PonE were independent on the gender or age in control group. Average values of Carb and BchE activities of directly and indirectly exposed workers were lower than those in control group respectively. PonE activity in directly exposed group was lower than that in control group. AChE activity in directly exposed group was lower than that in indirectly exposed group. All the differences were significant (P < 0.01). In the direct exposure group, the frequency of three variants of butyrylcholinesterase gene K (BCHE-K) polymorphism was 74.3%, 24.1% and 1.6% for UU, UK and KK respectively. Frequency of allele U and K was 0.863 and 0.137 respectively in the same group. Frequency of three variants of PON192 polymorphism was 15.0%, 45.5% and 39.5% for AA, AB and BB respectively in direct exposure group. Gene frequency of low activity (PON*A) and high activity (PON*B) was 0.378 and 0.622 respectively. Frequency of three variants of PON55 polymorphism was 96.2%, 3.8% and 0% for MM, LM and LL respectively in direct exposure group. Frequency of allele M and L was 0.981 and 0.019 respectively in the same group. The activity of PON was different in various genotypes of PON192 and PON55. CONCLUSION: The long-term exposure to OPs could inhibit the activities of CarbE, BchE, PonE and ACh E in different level. The genetic polymorphisms of PON192 and PON55 affect the activity of PonE, which is related to the detoxification of OPs and health impact.