中文摘要：

目的：研究依托咪酯对大鼠海马CA1区胞体动作电位及配体门控离子通道的影响。方法40只雄性大鼠快速断头，取出海马组织并用切片机切出400μm厚度的海马脑片，随机平分为4组：脂肪乳剂组（空白组）、依托咪酯组（对照组）和2个实验组（依托咪酯＋DIDS组与依托咪酯＋四乙铵组）。用全细胞电流钳技术给予不同强度的刺激，记录各组在不同刺激强度下对大鼠海马CA1区神经元动作电位发放的情况。结果脂肪乳剂不影响胞体动作电位的频率和幅值。10μmol· L-1依托咪酯脂肪乳剂能明显减少胞体动作电位的数目，同时动作电位的幅值也减小；逐渐增大刺激的强度，胞体动作电位产生的个数会相应地增加，但幅值无明显变化。 DIDS＋依托咪酯组在20 min后减少动作电位数目，且随着刺激强度的增加，动作电位衰减的时间逐渐延长。加入K＋通道阻滞剂（四乙胺）后，不影响依托咪酯对动作电位产生的抑制。结论依托咪酯脂肪乳剂抑制神经元动作电位发放的作用，可能主要通过开放氯通道、增加氯离子内流来实现；而钾通道对依托咪酯的抑制作用影响轻微。

英文摘要：

Objective To study the effect of etomidate emulsion on ac-tion potential and ligand -gated ion channel of hippocampal CA 1.Methods Forty male rats were decollated quickly , and then the hippo-campus were taken out and cut into 400 μm thickness of hippocampus slices using the slicing machine.The slices were divided into 4 groups randomly：lipid emulsion group （ n =10 ）; etomidate group （ n =10 ）;etomidate＋DIDS（4,4′-diisothiocyanato-2,2′-stilbenedisulfonic acid disodium salt hydrate ） group （ n=10 ） and etomidate＋TEA （ tetraethyl-ammonium） group （n=10）.The 4 groups were given lipid emulsion ,eto-midate,etomidate ＋DIDS （ Cl - channel blocker ） and etomidate ＋TEA （ K ＋channel blocker ） , respectively.Different stimulus intensities were give by current clamp technique and the impact of action potential firing were recorded.Results Intralipid did not change the number or ampli-tude of action potential.As the time incubated by etomidate was post-poned , the sum and amplitude of action potential in the soma of the hipp-ocampal CA1 neurons obviously reduced.When the stimulus intensity was augmented little by little , the sum of action potential firing should be notably increased but the amplitude of action potential had not obviouslychanged.DIDS plus etomidate reduced the sum of action potential after 20 min.With the stimulus intensity increasing , the degenerative time of action potential increased gradually.The last group joined with TEA which blocks potassium ion channel did not affect the suppression function of etomidate.Conclusion Etomidate emulsion may finally inhibit action potential through opening Cl -channel in order to increase Cl -internal flow to achieve general anesthesia.K＋channel may have few effects on this process.