Coactivation of multiple tightly coupled calcium channels triggers spontaneous release of GABA
Courtney Williams1, Wenyan Chen, Chia-Hsueh Lee
1Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, Oregon, USA.
Abstract:
Voltage-activated Ca(2+) channels (VACCs) mediate Ca(2+) influx to trigger action potential-evoked neurotransmitter release, but the mechanism by which Ca(2+) regulates spontaneous transmission is unclear. We found that VACCs are the major physiological triggers for spontaneous release at mouse neocortical inhibitory synapses. Moreover, despite the absence of a synchronizing action potential, we found that spontaneous fusion of a GABA-containing vesicle required the activation of multiple tightly coupled VACCs of variable type.
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