QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (22) Citing Articles via Google Scholar Google Scholar Articles by Willard, A. L. Search for Related Content PubMed PubMed Citation Articles by Willard, A. L.

 Previous Article  |  Next Article 

Journal of Neuroscience, Vol 10, 1025-1034, Copyright © 1990 by Society for Neuroscience

ARTICLE

A vasoactive intestinal peptide-like cotransmitter at cholinergic synapses between rat myenteric neurons in cell culture

AL Willard
Department of Physiology, University of North Carolina, Chapel Hill 27599.

Intracellular recording and immunochemical techniques were used to study synaptic transmission between individual pairs of rat myenteric plexus neurons in cell culture. This report describes the synaptic connections made by "dual function" presynaptic neurons that evoked slow postsynaptic depolarizations (slow EPSPs) in the same neurons in which they also evoked fast nicotinic cholinergic EPSPs. The slow EPSPs occurred only when presynaptic neurons were stimulated at frequencies of 5 Hz or higher. During the slow EPSPs, slope input resistance increased. The slow EPSPs were not detectably voltage-dependent, and they reversed sign at the estimated K+ equilibrium potential, suggesting that they resulted from a synaptically mediated decrease in resting K+ conductance. Several lines of evidence suggested that dual- function neurons evoke slow EPSPs by releasing a vasoactive intestinal peptide (VIP)-like cotransmitter. (1) Immunocytochemical staining revealed VIP-like immunoreactivity in all physiologically identified dual-function neurons. (2) Responses to exogenously applied VIP mimicked the slow EPSPs. (3) Superfusion of cultures with anti-VIP antisera blocked the slow EPSPs reversibly, as did application of desensitizing doses of VIP. These findings suggest that during periods of increased activity, subsets of cholinergic myenteric neurons release a VIP-like cotransmitter that enhances postsynaptic excitability. The effects of the cotransmitter may help to compensate for decreases in nicotinic EPSPs that occur during increased presynaptic activity.

This article has been cited by other articles:

				M. D. Whim, H. Niemann, and L. K. Kaczmarek The Secretion of Classical and Peptide Cotransmitters from a Single Presynaptic Neuron Involves a Synaptobrevin-Like Molecule J. Neurosci., April 1, 1997; 17(7): 2338 - 2347. [Abstract] [Full Text] [PDF]

				F. S. Vilim, D. A. Price, W. Lesser, I. Kupfermann, and K. R. Weiss Costorage and Corelease of Modulatory Peptide Cotransmitters with Partially Antagonistic Actions on the Accessory Radula Closer Muscle of Aplysia californica J. Neurosci., December 15, 1996; 16(24): 8092 - 8104. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help