临床浓度的依托咪酯对脊髓腹角神经元GABA和甘氨酸电流的作用  

Effect of etomidate with clinic concentration on GABA-and Gly-induced currents in spinal cord ventral horn neurons

作　　者：甄骋 靳娜 杨鑫宇 李妍 储婉玉 张环环[3] 徐爱萍 郑超[1] ZHEN Cheng;JIN Na;YANG Xinyu;LI Yan;CHU Wanyu;ZHANG Huanhuan;XU Aiping;ZHENG Chao(Neurobiology Laboratory,Wannan Medical College,Wuhu 241002,China)

机构地区：[1]皖南医学院神经生物学研究室,安徽芜湖241002 [2]皖南医学院细胞电生理研究室,安徽芜湖241002 [3]皖南医学院心理生理学研究室,安徽芜湖241002

出　　处：《皖南医学院学报》2023年第2期108-111,共4页Journal of Wannan Medical College

基　　金：国家自然科学基金项目(31200828);安徽省自然科学基金面上项目(2108085MC91);安徽省高校学科拔尖人才学术资助项目(gxbjZD2021061);安徽省高等学校自然科学研究重点项目(KJ2019A0411)。

摘　　要：目的:研究临床浓度依托咪酯(ET)对脊髓腹角神经元γ-氨基丁酸(GABA)诱导的电流和甘氨酸(Gly)诱导的电流的幅度及动力学指标的影响。方法:以7~14日龄的新生SD大鼠作为实验动物,将含腰骶膨大的脊髓切成厚度为300~500μm的薄片,经酶解消化后,机械吹打含腹角的切片,分离出单个神经元后进行穿孔膜片钳记录。在电压钳模式下(V H=-70 mV),分别使用GABA(0.1 mmol/L)和Gly(30.0μmol/L)在分离的脊髓腹角神经元上诱发出电流,并研究临床浓度的ET对这两种电流的峰电流、稳态电流的幅度和动力学指标的影响。结果:相当于临床浓度的3.0μmol/L的ET自身无法在分离的脊髓腹角神经元上诱发出电流。但使用3.0μmol/L的ET对记录的神经元预处理2 min后,与对照电流相比,能够增大GABA峰电流幅度和稳态电流幅度(P<0.01)。使用3.0μmol/L的ET预处理2 min后,与对照电流相比,能够增大Gly峰电流幅度和稳态电流幅度(P<0.01)。同时,3.0μmol/L的ET预处理2 min缩短了GABA电流的上升时间(RT)(P<0.01),而延长了其衰减时间(DT)(P<0.01)。使用相同浓度的ET预处理2 min后,Gly电流的RT缩短(P<0.01)而DT延长(P<0.01)。结论:临床浓度的ET对脊髓腹角神经元的GABA和Gly峰电流和稳态电流的幅度皆有增强作用,并且对GABA电流和Gly电流这两种电流的激活和失敏动力学指标皆具有差异性影响。Objective:To investigate the effects of etomidate(ET)with clinic concentration on the amplitudes and dynamics index ofγ-aminobutyric acid(GABA)-and glycine(Gly)-induced currents in spinal cord ventral horn neurons.Methods:Neonatal SD rats(aged 7-14 d)were used in this experiment.Spinal cord slices of lumbosacral enlargement with thickness of 300-500μm were prepared and digested by enzyme,then the spinal cord ventral horn neurons were acutely isolated,on which perforated patch-clamp recordings were performed.In the voltage-clamp mode(V H=-70 mV),GABA(0.1 mmol/L)and Gly(30.0μmol/L)were respectively applied to induce currents in the isolated ventral horn neurons,and the effects of pretreatment with etomidate on the peak current amplitudes,steady-state current amplitudes and dynamics indices of these two types of currents were examined.Results:3.0μmol/L(equivalent to clinic concentration)ET failed to induce currents by itself in isolated spinal cord ventral horn neurons.After pretreatment with 3.0μmol/L ET for 2 min,GABA-induced peak currents and steady-state currents were increased(P<0.01),and Gly-induced peak currents and steady-state currents were also increased(P<0.01).Pretreatment with 3.0μmol/L ET shortened rise time(RT)of GABA currents(P<0.01)and prolonged decay time(DT)(P<0.01)as well as RT of Gly currents(P<0.01),and prolonged DT(P<0.01).Conclusion:Etomidate with clinic concentration can lead to enhanced effect on the amplitudes of both GABA-and Gly-induced peak currents and steady-state currents,and differentially affect the dynamics index(activation and desensitization)of GABA-and Gly-induced currents in spinal cord ventral horn neurons.

关 键 词：依托咪酯 GABA电流 Gly电流 脊髓腹角神经元 膜片钳记录 

分 类 号：R614[医药卫生—麻醉学] R338[医药卫生—外科学] R-332[医药卫生—临床医学]