乐果染毒对大鼠心血管系统的影响  

Effects on cardiovascular system in rats orally exposed to dimethoate

作　　者：徐甫[1] 张雪梅[1] 顾锡安[1] 周志俊[1] 

机构地区：[1]复旦大学公共卫生学院/教育部公共卫生安全重点实验室,上海200032

出　　处：《中国工业医学杂志》2010年第5期327-331,共5页Chinese Journal of Industrial Medicine

基　　金：国家十一五支撑项目(2006AB106B01)

摘　　要：目的观察乐果28天染毒对雄性SD大鼠心血管系统的影响,探讨乐果诱导其毒性的可能机制。方法雄性SD大鼠,乐果灌胃染毒,每天1次,连续28 d。每5天测定大鼠外周血AChE活力,每周测定2次血压。染毒结束后测定心脏AChE、Ca2+-ATPase和Na+-K+-ATPase酶活力,以及M2受体、Ca2+-ATPase和兰尼碱受体基因表达水平。结果乐果28天染毒SD大鼠心肌和外周血AChE活力显著下降。染毒初期,乐果可以引起SD大鼠血压升高,染毒剂量越高,血压升高越显著,但到染毒后期,血压呈现下降趋势。染毒结束后,SD大鼠心肌Na+-K+-ATPase和Ca2+-ATPase活力以及mRNA表达,均未见显著性改变,50 mg/kg染毒组大鼠的M2受体和RyR的mRNA表达均明显下调,分别达到0.64±0.02和0.61±0.03。结论接触一定剂量的乐果可以引起SD大鼠血压的改变,可能同M2受体基因和兰尼碱受体基因表达水平有关。Objective To explore the effect of dimethoate on cardiovascular system in SD rats after 28 days exposure orally and its potential mechanism.Methods Male SD rats were daily given dimethoate by gavage for continuous 28 days.Activity of AChE in peripheral blood was measured every five days,blood pressure was determined twice a week.At the end of exposure,activities of Ca2＋-ATPase and Na＋-K＋-ATPase,mRNA expression of muscarinic receptors,ATPase and ryanodine receptors in the heart were measured.Results Compared to controls,activities of AChE in the peripheral blood and cardiac muscles of exposed SD rats were significantly decreased.Although there was a decreased tendency at the end of exposure,blood pressure in the exposed SD rats increased significantly along with the incremental doses at the initial stage of exposure.At the end of exposure,the difference of activity and gene expression of ATPase in both serum and cardiac muscles between the exposed rats and control were not significant.However,the mRNA expression of muscarinic and ryanodine receptors（0.64±0.02 and 0.61±0.03,respectively）in cardiac muscles of SD rats exposed to 50 mg/kg dimethoate were decreased significantly.Conclusion It is suggested that subacute exposure to dimethoate might affect blood pressure of rats,which might relate to the changes of muscarinic receptor and ryanodine receptor.

关 键 词：乐果 血压 乙酰胆碱酯酶 ATP酶 兰尼碱受体 

分 类 号：R595.4[医药卫生—内科学]