Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

New data show that 5-hydroxytryptamine (5-HT) neurons of the dorsal raphe nucleus (DRN) are subject to feedback control from 5-HT2 receptors, but the circuitry involved is uncertain. This study investigated whether 5-HT2 receptor agonism activates DRN gamma-aminobutyric acid (GABA) neurons, which are known to inhibit neighbouring 5-HT neurons. Systemic administration of the 5-HT2 receptor agonist, DOI, caused a striking increase in Fos-immunoreactivity in the DRN. This effect was abolished by the 5-HT2 antagonists ritanserin and MDL 100907, but not SB 206553, indicating the involvement of 5-HT2A receptors. Importantly, DOI-induced Fos-immunoreactivity in the DRN was extensively colocalized in GAD67-immunoreactive neurons. These findings suggest that activated local GABA neurons may play an important role in 5-HT2 receptor-mediated feedback control of DRN 5-HT neurons.

Type

Journal article

Journal

Neuroreport

Publication Date

21/06/2005

Volume

16

Pages

891 - 896

Keywords

Amphetamines, Analysis of Variance, Animals, Cell Count, Feedback, Fluorobenzenes, Gene Expression Regulation, Glutamate Decarboxylase, Immunohistochemistry, Isoenzymes, Male, Neurons, Oncogene Proteins v-fos, Piperidines, Raphe Nuclei, Rats, Rats, Sprague-Dawley, Serotonin, Serotonin Antagonists, Serotonin Receptor Agonists, gamma-Aminobutyric Acid