Elsevier

Neuroscience Letters

Volume 204, Issue 3, 9 February 1996, Pages 161-164
Neuroscience Letters

A 5-hydroxytryptamine lesion markedly reduces the incidence of burst-firing dorsal raphe neurones in the rat

https://doi.org/10.1016/0304-3940(96)12333-8Get rights and content

Abstract

Recently, we described neurones in the rat dorsal raphe nucleus (DRN) with electrophysiological characteristics typical of 5-hydoxytryptamine (5-HT) neurones except that the neurones fired brief burst. Here we report the effect of 5-HT lesions on the incidence of these burst-firing neurones. In vivo extracellular recordings revealed that in rats pretreated with the selective 5-HT neurotoxin, 5,7-dihydroxytryptamine, the occurrence of typical 5-HT neurones was significantly decreased (80%) compared to controls. In these 5-HT lesioned animals, the number of the burst-firing DRN neurones was also significantly reduced (91%). Neurones previously characterised as not containing 5-HT, were not altered by the lesion. These data are further evidence to support our hypothesis that burst-firing neurones in the DRN contain 5-HT.

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This work was supported by the Medical Research Council (UK).

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