QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal 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 Google Scholar Google Scholar Articles by Wildman, M. Articles by Burrows, M. Search for Related Content PubMed PubMed Citation Articles by Wildman, M. Articles by Burrows, M.

The Journal of Experimental Biology 205, 3651-3659 (2002)
Copyright © 2002 The Company of Biologists Limited

GABA-like immunoreactivity in nonspiking interneurons of the locust metathoracic ganglion

M. Wildman, S. R. Ott and M. Burrows^*

Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
Present address: School of Biological Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK

^* Author for correspondence (e-mail: mb135{at}hermes.cam.ac.uk)

Accepted 22 August 2002

Nonspiking interneurons are important components of the premotor circuitry in the thoracic ganglia of insects. Their action on postsynaptic neurons appears to be predominantly inhibitory, but it is not known which transmitter(s) they use. Here, we demonstrate that many but not all nonspiking local interneurons in the locust metathoracic ganglion are immunopositive for GABA (-aminobutyric acid). Interneurons were impaled with intracellular microelectrodes and were shown physiologically to be nonspiking. They were further characterized by defining their effects on known leg motor neurons when their membrane potential was manipulated by current injection. Lucifer Yellow was then injected into these interneurons to reveal their cell bodies and the morphology of their branches. Some could be recognised as individuals by comparison with previous detailed descriptions. Ganglia were then processed for GABA immunohistochemistry. Fifteen of the 17 nonspiking interneurons studied were immunopositive for GABA, but two were not. The results suggest that the majority of these interneurons might exert their well-characterized effects on other neurons through the release of GABA but that some appear to use a transmitter other than GABA. These nonspiking interneurons are therefore not an homogeneous population with regard to their putative transmitter.

Key words: GABA, immunohistochemistry, premotor interneurons, motor control, locust, Schistocerca gregaria

This article has been cited by other articles:

				S. M. Rogers, T. Matheson, K. Sasaki, K. Kendrick, S. J. Simpson, and M. Burrows Substantial changes in central nervous system neurotransmitters and neuromodulators accompany phase change in the locust J. Exp. Biol., September 15, 2004; 207(20): 3603 - 3617. [Abstract] [Full Text] [PDF]