【摘要】 用细胞内电位记录技术,以离体蟾蜍交感链为标本,观察了尖吻蝮蛇毒(AAV)的神经毒性作用。结果表明,该蛇毒(10-200μg/ml)对交感神经元的静息电位、膜电阻和膜电容没有显著的作用,对动作电位形状也无可测出的影响,但能使阈电位轻皮升高,即使神经元兴奋性稍降低。AAV(>25μg/ml)对胆碱能性的快兴奋性突触后电位有剂量依从性的,部分可逆性的抑制作用。其作用机制至少应部分归之于AAV对突触后膜上的N型胆碱能受体的阻断作用。本研究发现的AAV神经毒性作用可能有一定实践意义。更多还原

【Abstract】 The neurotoxic actions of the snake venom, Agkistrodon Acutus Venom ( AAV ) . were examined on the toad sympathetic ganglion neurons by an intracellular recording technique. AAV (10-200ng/ml) showed no appreciable effects on the resting potential, input resistance, membrane capacitance as well as the trajectory of the action potential.lt slightly raised tke threshold potential for discharges, thus decreased the neuronal excitability. The major action of the venom ( >25μg/mi ) was found to be an inhibition on the fast excitatory postsynaptic potential ( f-EPSP), which is known to be mediated by a transmitter of ACh and a receptor of nicotinic type. The inhibition was dose-dependent and partially reversible. The mechanisms underlying this inhibition might be postsynaptic at least in portion, namely,AAV probably blocked the nlcotinic receptor on the postsynaptic membrane, since a depolarization induced by locally ejected ACh was also suppressed by AAV (> 10μg/ml ) . The possible role of neurotoxic action of AAV in severe cases of the snake bite was discussed.更多还原