Ca2+ influx through voltage gated Ca2+ channels Authored: Mahajan, SS, 2008-01-14 16:01:52 Ca2+ influx from the extracellular space into the presynaptic neuron through the Voltage Gated Ca2+ Channels (VGCC), is dependant on the arrival of an action potential at the synaptic bulb. The vesicle fusion and subsequent release of glutamate into the synapse is triggered by this influx of Ca2+. The VGCCs involved here could be of the N, P/Q or R type.<p>Hyperpolarization of the cell membrane due to KIR3 potassium channel activity inhibits this influx of Ca2+. Edited: Gillespie, ME, 2009-11-19 Pubmed8825650 Reactome Database ID Release 43210420 Reactome, http://www.reactome.org ReactomeREACT_12594 Reviewed: Kavalali, E, 2008-04-24 16:31:34