Wali F A
London Hospital Medical College, Anaesthetics Unit, University of London, Whitechapel, England.
Acta Physiol Hung. 1988;71(1):61-8.
The effect of ganglion blocking agents, hexamethonium and tubocurarine, on post-train facilitation and ganglionic transmission was studied and compared in isolated superior cervical ganglion of the rabbit, using electrophysiological technique--the conditioning-testing methodology. The preganglionic nerve trunk was stimulated, with either a single unconditioned stimulus (UR)-or a train of conditioning stimuli at 10 or 30 Hz, followed by a post-train test stimulus (PTR). The transmitted postganglionic, compound action potential (PCAP) was recorded following single and trains of stimuli, in the presence and absence of ganglion blocking drugs, hexamethonium (1-100 microM) and tubocurarine (1-100 microM). Hexamethonium and tubocurarine produced concentration-dependent reduction in the amplitude of the transmitted PCAP, increased post-train facilitation values and proportionately reduced those of the subliminal fringe (SF). The mean IC50 values (concentration to produce 50% block of PCAP) of hexamethonium and tubocurarine-induced blockade of the single unconditioned response were 15 +/- 1 microM and 26 +/- 2 microM (n = 6, P less than 0.01) respectively. A dose-ratio (tubocurarine)/hexamethonium) of 1.7 was obtained.
利用电生理技术——条件-测试方法，在兔离体颈上神经节中研究并比较了神经节阻断剂六甲铵和筒箭毒碱对训练后易化和神经节传递的影响。刺激节前神经干，采用单个非条件刺激（UR）或10或30Hz的一串条件刺激，随后进行训练后测试刺激（PTR）。在有无神经节阻断药物六甲铵（1 - 100μM）和筒箭毒碱（1 - 100μM）的情况下，记录单个刺激和一串刺激后所传递的节后复合动作电位（PCAP）。六甲铵和筒箭毒碱使所传递的PCAP幅度产生浓度依赖性降低，增加训练后易化值，并相应降低阈下边缘（SF）的值。六甲铵和筒箭毒碱对单个非条件反应的阻断的平均IC50值（产生50% PCAP阻断的浓度）分别为15±1μM和26±2μM（n = 6，P < 0.01）。得到剂量比（筒箭毒碱/六甲铵）为1.7。
