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Coactivation of multiple tightly coupled calcium channels triggers spontaneous release of GABA.

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.

SUBMITTER: Williams C

PROVIDER: S-EPMC3431448 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Coactivation of multiple tightly coupled calcium channels triggers spontaneous release of GABA.

Williams Courtney C Chen Wenyan W Lee Chia-Hsueh CH Yaeger Daniel D Vyleta Nicholas P NP Smith Stephen M SM

Nature neuroscience 20120729 9

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 tightl ...[more]

PMID: 22842148

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