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Evidence for ectopic neurotransmission at a neuronal synapse.

ABSTRACT: Neurotransmitter release is well known to occur at specialized synaptic regions that include presynaptic active zones and postsynaptic densities. At cholinergic synapses in the chick ciliary ganglion, however, membrane formations and physiological measurements suggest that release distant from postsynaptic densities can activate the predominantly extrasynaptic alpha7 nicotinic receptor subtype. We explored such ectopic neurotransmission with a novel model synapse that combines Monte Carlo simulations with high-resolution serial electron microscopic tomography. Simulated synaptic activity is consistent with experimental recordings of miniature excitatory postsynaptic currents only when ectopic transmission is included in the model, broadening the possibilities for mechanisms of neuronal communication.

SUBMITTER: Coggan JS

PROVIDER: S-EPMC2915764 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature

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Evidence for ectopic neurotransmission at a neuronal synapse.

Coggan Jay S JS Bartol Thomas M TM Esquenazi Eduardo E Stiles Joel R JR Lamont Stephan S Martone Maryann E ME Berg Darwin K DK Ellisman Mark H MH Sejnowski Terrence J TJ

Science (New York, N.Y.) 20050701 5733

Neurotransmitter release is well known to occur at specialized synaptic regions that include presynaptic active zones and postsynaptic densities. At cholinergic synapses in the chick ciliary ganglion, however, membrane formations and physiological measurements suggest that release distant from postsynaptic densities can activate the predominantly extrasynaptic alpha7 nicotinic receptor subtype. We explored such ectopic neurotransmission with a novel model synapse that combines Monte Carlo simula ...[more]

PMID: 16020730

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