眼镜蛇神经毒素对豚鼠颈上神经节烟碱传递的易化作用(英文)

本研究用离休豚鼠颈上神经节细胞内生物电记录技术,对眼镜蛇毒神经毒素对交感神经节突触传递影响进行探讨。研究首次表明,眼镜蛇神经毒素对交感神经突触前ACh的释放有易化作用。

Facilitation of nicotinic transmission in guinea pig isolated superior cervical ganglion cells by cobrotoxin

The effect of cobrotoxin on neurons and on ganglionic transmission of the isolated superior cervical ganglion of the guinea pig was investigated by means of intracellular recording techniques.Cobrotoxin(0.1~10μmol/L)increased the amplitude and duration of fast excitatory post-synaptic potential evoked by the stimulation of the prcganglionic nerve.The facilitatory effect persisted for over 2 h following the removal of the toxin from bathing solution and could be abolished by d-Tc.At the concentration of 10μmol/L or more,cobrotoxin inducing facilitation was often associated with random discharges of miniature EPSPs which were reduced in low Ca2+solution and were blocked by d-Tc and atropine.The ACh and Carb depolarizations were not affected by cobrotoxin.This study demonstrates that cobrotoxin may have a presyn-aptic effect on ACh release.