依托咪酯激活大鼠骶髓后连合核神经元GABA_A门控氯通道电流  

Activation of GABA_(A) receptor-gated chloride currents by etomidate in rat sacral dorsal commissural neurons

作　　者：洪桢[1] 王殿仕[1] 李继硕[1] 

机构地区：[1]第四军医大学解剖学教研室暨梁銶琚脑研究中心,陕西西安710032

出　　处：《中国神经科学杂志》2004年第4期266-269,共4页

基　　金：国家自然科学基金资助项目(30300077);第四军医大学"后备人才"基金资助

摘　　要：目的　 研究依托咪酯 (etomidate ,ET)在急性分离的大鼠骶髓后连合核 (sacraldorsalcommissuralnucleus,SDCN)神经元的药理学特性。方法　采用制霉菌素穿孔膜片钳全细胞记录。结果　在大鼠SDCN神经元 ,ET(10～ 30 0 0 μmol/L)在钳制电位为 - 40mV时 ,可引起内向电流 (IET) ,EC50 为 (33.35± 3.0 7) μmol/L ,该电流可被GABAA受体拮抗剂荷包牡丹碱 (bicuculline)及氯通道阻滞剂印防己毒素 (picrotoxin)以浓度依赖方式所阻断。结论　ET在大鼠SDCN神经元可通过作用于GABAA受体而诱发氯通道电流 。ObjectiveTo investigate the pharmacological properties of etomidate (ET) in the dissociated rat sacral dorsal commissural nucleus (SDCN) neurons. MethodsNystatin perforated patch recording technique under voltage-clamp conditions was used. ResultsAt the holding potential of -40 mV, ET evoked inward current (I_(ET)) over the concentration range of 10 μmol/L to 3 mmol/L with the EC_(50) value of (33.35 ± 3.07) μmol/L. The I_(ET) was suppressed by bicuculline, the selective GABA_(A) receptor antagonist, and picrotoxin a selective blocker of Cl^(-) channel, in a concentration-dependent manner. ConclusionThe results indicate that ET acts on GABA_(A) receptors to result in the opening of the Cl^(-) channels in the SDCN neurons, which may contribute to its general anesthesia at spinal level.

关 键 词：依托咪酯 GABAA受体 氯通道电流 制霉菌素穿孔膜片钳 骶髓后连合核 

分 类 号：R96[医药卫生—药理学]