Slow synaptic transmission mediated by 5-HT_(1P) receptor in sympathetic ganalion of guinea pig / 中国药理学通报

ABSTRACT

AIM To investigate the effects of several 5-hydroxytryptamine(5-HT) subtype receptor antagonists on late slow excitatory postsynaptic potential(LS-EPSP) of the neurons of guinea pig inferior mesenteric ganglion(IMG). METHODS Intracellular recordings were made from neurons of the isolated guinea pig IMG. RESULTS Cyproheptadine and BRL 24924 suppressed LS-EPSP of 5-HT sensitive neurons reversibly, while mianserin, MDL 72222 and spiperone showed no significant effect. Continuous superfusion of IMG with MCPP suppressed LS-EPSP of 5-HT sensitive neurons by 5-HT 1P receptor desensitizated. CONCLUSION LS-EPSP of 5-HT sensitive neuron is mediated by 5-HT 1P subtype receptor.