Department of Anesthesiology

You are here

Control and plasticity of the presynaptic action potential waveform at small CNS nerve terminals.

TitleControl and plasticity of the presynaptic action potential waveform at small CNS nerve terminals.
Publication TypeJournal Article
Year of Publication2014
AuthorsHoppa MB, Gouzer G, Armbruster M, Ryan TA
JournalNeuron
Volume84
Issue4
Pagination778-89
Date Published2014 Nov 19
ISSN1097-4199
KeywordsAction Potentials, Animals, Calcium, Calcium Channels, Hippocampus, Neuronal Plasticity, Neurons, Potassium Channels, Presynaptic Terminals, Rats, Rats, Sprague-Dawley, Synapses
Abstract

The steep dependence of exocytosis on Ca(2+) entry at nerve terminals implies that voltage control of both Ca(2+) channel opening and the driving force for Ca(2+) entry are powerful levers in sculpting synaptic efficacy. Using fast, genetically encoded voltage indicators in dissociated primary neurons, we show that at small nerve terminals K(+) channels constrain the peak voltage of the presynaptic action potential (APSYN) to values much lower than those at cell somas. This key APSYN property additionally shows adaptive plasticity: manipulations that increase presynaptic Ca(2+) channel abundance and release probability result in a commensurate lowering of the APSYN peak and narrowing of the waveform, while manipulations that decrease presynaptic Ca(2+) channel abundance do the opposite. This modulation is eliminated upon blockade of Kv3.1 and Kv1 channels. Our studies thus reveal that adaptive plasticity in the APSYN waveform serves as an important regulator of synaptic function.

DOI10.1016/j.neuron.2014.09.038
Alternate JournalNeuron
PubMed ID25447742
PubMed Central IDPMC4283217
Grant ListMH085783 / MH / NIMH NIH HHS / United States
R01 MH085783 / MH / NIMH NIH HHS / United States