Rapid activation of dormant presynaptic terminals by phorbol esters.

Citation data:

The Journal of neuroscience : the official journal of the Society for Neuroscience, ISSN: 1529-2401, Vol: 30, Issue: 30, Page: 10048-60

Publication Year:
2010
Usage 86
Abstract Views 65
Downloads 21
Captures 137
Readers 134
Exports-Saves 3
Citations 7
Citation Indexes 7
Repository URL:
https://digitalcommons.wustl.edu/open_access_pubs/232
PMID:
20668189
DOI:
10.1523/jneurosci.1159-10.2010
PMCID:
PMC2921706
Author(s):
Chang, Chun Yun; Jiang, Xiaoping; Moulder, Krista L; Mennerick, Steven
Publisher(s):
Society for Neuroscience
Tags:
Neuroscience
article description
Presynaptic stimulation stochastically recruits transmission according to the release probability (P(r)) of synapses. The majority of central synapses have relatively low P(r), which includes synapses that are completely quiescent presynaptically. The presence of presynaptically dormant versus active terminals presumably increases synaptic malleability when conditions demand synaptic strengthening or weakening, perhaps by triggering second messenger signals. However, whether modulator-mediated potentiation involves recruitment of transmission from dormant terminals remains unclear. Here, by combining electrophysiological and fluorescence imaging approaches, we uncovered rapid presynaptic awakening by select synaptic modulators. A phorbol ester phorbol 12,13-dibutyrate (PDBu) (a diacylglycerol analog), but not forskolin (an adenylyl cyclase activator) or elevated extracellular calcium, recruited neurotransmission from presynaptically dormant synapses. This effect was not dependent on protein kinase C activation. After PDBu-induced awakening, these previously dormant terminals had a synaptic P(r) spectrum similar to basally active synapses naive to PDBu treatment. Dormant terminals did not seem to have properties of nascent or immature synapses, judged by NR2B NMDAR (NMDA receptor) receptor subunit contribution after PDBu-stimulated awakening. Strikingly, synapses rendered inactive by prolonged depolarization, unlike basally dormant synapses, were not awakened by PDBu. These results suggest that the initial release competence of synapses can dictate the acute response to second messenger modulation, and the results suggest multiple pathways to presynaptic dormancy and awakening.