罗库溴铵对鼠海马皮层锥体神经元乙酰胆碱受体的影响

Effect of rocuronium on acetylcholine receptor in cone neurons of hippocampal cortex in rats

目的 观察罗库溴铵对鼠海马皮层锥体神经元乙酰胆碱受体(AchR)通道电生理学的影响。方法应用急性分离法与膜片钳贴附式单通道记录技术,观测不同浓度罗库溴铵(0、0.05、0.1、0.2、0.4mmol·L-1)或与0.1 mmol·L-1阿托品对SD大鼠海马皮层锥体神经元胞体上AchR通道电生理学参数的作用。结果 (1)R0.05组中电导、开放概率(P0)、短时程开放时间常数(τ01)大于或长于对照组(P<0.05或0.01),长时程开放时间常数(τ02)、短时程关闭时间常数(τc1)、长时程关闭时间常数(τc2)则无统计学差异(P>0.05);其余各组6项参数均大于或长于对照组(P<0.05或0.01)。(2)同时加入罗库溴铵与阿托品,R0.05组各参数与对照组比较无统计学差异(P>0.05);其余各组6项参数(R0.1组中除τ01外)均大于或长于对照组(P<0.05或0.01)。结论 0.05～0.4 mmol·L-1罗库溴铵可不同程度致使鼠海马皮层锥体神经元AchR通道兴奋;浓度为0.05 mmol·L-1时可能主要作用于其毒蕈碱型AchR;浓度达0.1～0.4mmol·L-1时则可能以兴奋烟碱型AchR通道为主。研究结果提示,罗库溴铵一旦透过受损害的血脑屏障,可能引起中枢系统的不良反应。

Objective To investigate the effect of rocuronium of on the function of acetylcholine receptor (AchR)/channel in cone neurons of hippocampal cortex in rats.Methods SD rats of both sexes (2-5 days old) were killed by decapitation. Brain was immediately removed and hippocampal cortex was cut into slices which were incubated in decalcified and magnesium-free artificial cerebro-spinal fluid (CSF) and mechanically dissociated and then digested in artificial CFS containing 2.5% trypsin. Cell suspension was prepared. The AchR/channel function was studied in the absence and presence of various concentrations of rocuronium (0, 0.05, 0.1, 0.2, 0.4mmol· L-1) and/or atropine 0.1 mmol ·L-1 using patch clamp technique.Results (1) The conductance, open probability (P0) and short term open constant (τ01) were significantly higher in R-0.05 group than those in the control group (R-0) , but there was no significant difference in long term open constant (τ02) , short term close constant( (τc1) and long term close constant(τc2) between the two groups. The conductance, P0 ,τ01 ,τ02 , τc1, and τc2 were significantly longer or higher in R-0.0, 0.2 and 0.4 groups than those in control group. (2) There was no significant difference in the conductance, P0 , τ01 , τ02 , τc1 , and τc2, between R-0.5 and control group but those in R-0.0, 0.2 and 0.4 groups were significantly higher or longer than control group, when rocuronium was used with atropine. Conclusions AchR/channel ( muscarinic and nicotinic ) in cone neuron of hippocampal cortex were excited by different concentrations of rocuronium. The results suggest that adverse effect may be induced on CNS by rocuronium in case it permeates the injured blood-brain barrier.