对吸入麻醉药敏感性不同的果蝇幼虫中枢神经元钾通道的研究  

Investigation of potassium channels on the larval cerebral neurons of drosophila melanogaster with different sensitivity to volatile anesthetics

作　　者：刘洋[1,2] 罗南富[1] 廖大清[1] 刘进[1] 

机构地区：[1]四川大学华西医院麻醉与危重急救研究室,成都市610041 [2]四川省南充市川北医学院附属医院麻醉科

出　　处：《临床麻醉学杂志》2008年第10期886-888,共3页Journal of Clinical Anesthesiology

基　　金：国家自然科学基金(30070732);教育部博士点基金

摘　　要：目的以果蝇为动物模型,利用膜片钳技术探讨钾通道在吸入麻醉药作用机制中的地位。方法以酶解和血清孵育的方法分离制备敏感(S)、野生(H)和对七氟醚耐药(R)果蝇晚三龄幼虫脑神经元,以膜片钳技术记录其全细胞钾电流,并对电流进行单、双指数拟合,根据失活时间常数和电流幅值大小,将钾电流分为Ⅰ、Ⅱ、Ⅲ及Ⅳ型。结果三品系中,Ⅰ和Ⅱ型钾电流的峰值电流(Ipeak)和失活时间常数(τ1)差异无统计学意义;Ⅲ和Ⅳ型钾电流的Ipeak差异有统计学意义(P<0.05):S>H>R;Ⅳ型钾电流τ1差异有统计学意义(P<0.05):S=H>R;Ⅴ型钾电流(钙激活钾电流)的Ipeak差异有统计学意义(P<0.05):R>H>S。结论钾通道可能是吸入麻醉药七氟醚的中枢作用位点之一。Objective Drosophila was applied as animal model to investigate K^＋ channels targets for volatile anesthetics. Methods Three strains of Drosophila with high （S）,normal （H） and low （R） sensitivity to sevoflurane were applied. Cerebral neurons from the three strains of late third instar larvae of drosophila were obtained by acutely enzymatic digestion and incubation in fetal bovine serum. Whole-cell potassium currents on the cerebral neurons were detected using voltage-clamp recording technique. All the currents were classified into four types （type Ⅰ , Ⅱ , Ⅲ and Ⅳ ） based on time constants of inactivation （τ1,τ2 ） and relative amplitude （A1, A2 ） of exponential components obtained by single- or double exponential fitting. Results Ipeak and τ1 values of type Ⅰ and type Ⅱ currents were not significantly different among the three strains. Ipeak values of type Ⅲ currents were significantly different in the three strains （P〈0.05） in an order of Ipeak （S）〉 Ipeak （H）〉 Ipeak （R）. Ipeak and τ1 values of type Ⅳ currents were significantly different among the three strains （P〈 0.05） in an order of Ipeak （S）〉Ipeak（H）〉Ipeak （R） and τ1 （S） =τ1 （H）〉τ1 （R）. Ipeak values of IKc, （typeV） were significantly different among the three strains （P〈0.05） in an order of Ipeak （R） 〉Ipeak （H）S〉Ipeak （S）. Conclusion The results indicate that volatile anesthetics may act on K^＋ channels in the mechanisms of anesthesia.

关 键 词：果蝇 膜片钳技术 钾通道 吸入麻醉药 

分 类 号：R96[医药卫生—药理学]