Calcitonin gene-related peptide potentiates synaptic responses at developing neuromuscular junction

Calcitonin gene-related peptide (CGRP), a neuropeptide in presynaptic motor nerve terminals, promotes postsynaptic reaction in maturing neuromuscular networks by extending the bursting period of embryonic ACh channels. The effect of CRGP on ACh channels is simulated by dibutyryl-cyclic AMP and cAMP-dependent protein kinase, obstructed by peptide inhibitor PKA. Postsynaptic inhibitions by PKA narrowed the amplitude and decay time of spontaneous synaptic current. Prolonging the burst duration raises postsynaptic activity at the bginning of the development stage, when time resolution is not too crucial.