Target-specific short-term dynamics are important for the function of synapses in an oscillatory neural network

Document Type

Article

Publication Date

10-1-2005

Abstract

Short-term dynamics such as facilitation and depression are present in most synapses and are often target-specific even for synapses from the same type of neuron. We examine the dynamics and possible functions of two synapses from the same presynaptic neuron in the rhythmically active pyloric network of the spiny lobster. Using simultaneous recordings, we show that the synapses from the lateral pyloric (LP) neuron to the pyloric dilator (PD; a member of the pyloric pacemaker ensemble) and the pyloric constrictor (PY) neurons both show short-term depression. However, the postsynaptic potentials produced by the LP-to-PD synapse are larger in amplitude, depress less, and recover faster than those produced by the LP-to-PY synapse. The main function of the LP-to-PD synapse is to slow down the pyloric rhythm. However, in some cases, it slows down the rhythm only when it is fast and has no effect or to speeds up when it is slow. In contrast, the LP-to-PY synapse functions to delay the activity of the PY neuron; this delay increases as the cycle period becomes longer. Using a computational model, we show that the short-term dynamics of synaptic depression observed for each of these synapses are tailored to their individual functions and that replacing the dynamics of either synapse with the other would disrupt these functions. Together, the experimental and modeling results suggest that the target-specific features of short-term synaptic depression are functionally important for synapses efferent from the same presynaptic neuron. Copyright © 2005 The American Physiological Society.

Identifier

24944581588 (Scopus)

Publication Title

Journal of Neurophysiology

External Full Text Location

https://doi.org/10.1152/jn.00110.2005

ISSN

00223077

PubMed ID

15972837

First Page

2590

Last Page

2602

Issue

4

Volume

94

Grant

R01MH060605

Fund Ref

National Institute of Mental Health

This document is currently not available here.

Share

COinS