【摘要】 目的研究异丙酚、咪达唑仑分别复合芬太尼对大鼠海马锥体神经元γ-氨基丁酸A(GABAA)受体的作用,探讨复合麻醉的机制。方法采用酶-机械法急性分离出生3~10日龄SD大鼠的海马锥体神经元,采用全细胞膜片钳技术记录锥体神经元GABAA受体介导的Cl-电流(GABA电流,IGABA)。实验分为单纯异丙酚组(组Ⅰ)、异丙酚复合芬太尼组(组Ⅱ)、单纯咪达唑仑组(组Ⅲ)及咪达唑仑复合芬太尼组(组Ⅳ)。结果0.3~30.0μmol/L异丙酚(组Ⅰ、组Ⅱ)、0.03~100.0μmol/L咪达唑仑(组Ⅲ、组Ⅳ)能剂量依赖性地增强IGABA,两药的作用曲线呈钟形,3.0μmol/L时作用最强,与其他浓度的差异有显著性(P<0.05)。0.01μmol/L芬太尼抑制IGABA后,组Ⅱ3.0μmol/L异丙酚增强IGABA的作用较组Ⅰ更明显[电流增强率:组Ⅰ为(127.2±11.2)%,组Ⅱ为(212.5±14.9)%,P<0.05],组Ⅳ3.0μmol/L咪达唑仑的作用较组Ⅲ无明显改变(P>0.05)。结论芬太尼能够增强异丙酚对海马锥体神经元GABAA受体的作用,对咪唑安定的作用无影响。异丙酚、咪达唑仑复合芬太尼可能减轻芬太尼的神经兴奋性不良反应。更多还原

【Abstract】 Objective To observe the effects of propofol or midazolam combined with fentanyl on GABA_A receptor in acutely dissociated hippocampal pyramidal neurons of neonatal rats, so as to reveal the possible mechanism of the combined anesthesia. Methods Whole-cell patch-clamp technique was used to record the GABA_A receptor-induced currents (I_GABA) in four groups(n=5 of each), ie, propofol(groupⅠ), propofol combined with fentanyl(groupⅡ), midazolam (groupⅢ) and midazolam combined with fentanyl(groupⅣ). Results 0.3-30.0 μmol/L propofol (groupⅠ,Ⅱ) and 0.03-100.0 μmol/L midazolam (groupⅢ, Ⅳ) facilitated I_GABA with the greatest enhancement at 3.0 μmol/L of each (P<0.05). Following 0.01 μmol/L fentanyl pretreatment for 10 minutes, the facilitation of I_GABA by 3.0 μmol/L propofol increased significantly [(127.2±11.2)% (groupⅠ) vs (212.5±14.9)% (groupⅡ), P<0.05, n=5], whereas the effects of midazolam were not changed by fentanyl pretreatment [(158.2±34.0)% (groupⅢ) vs (116.3±46.0)% (groupⅣ), P>0.05, n=5]. Conclusion Fentanyl can enhance the effects of propofol on GABA_A receptor, but not influence those of midazolam. Propofol or midazolam combined with fentanyl may prevent the neuroexcitatory effects of fentanyl, supporting their use in combination for clinical anesthesia.更多还原