English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/33045
Title: An autoradiographic study of the influence of pindolol upon [35S]GTPgammaS binding in rat, guinea pig and human brain
Authors: Serrats, Jordi; Artigas, Francesc ; Mengod Los Arcos, Guadalupe ; Cortés, Roser
Keywords: Antidepressants
dorsal raphe
5-HT1A autoreceptors
Issue Date: Mar-2004
Publisher: Cambridge University Press
Citation: International Journal of Neuro-Psychopharmacology 7 (1) : 27-34 (2004)
Abstract: The 5-HT1A/beta-adrenoceptor ligand (+/-)pindolol has been used in clinical trials to enhance the antidepressant effect of selective serotonin (5-HT) reuptake inhibitors (SSRIs). The accelerating effect of (+/-)pindolol is thought to derive from its blockade of the SSRI-induced, 5-HT1A autoreceptor-mediated inhibition of serotonergic cell firing and 5-HT release. However, controversial results have been reported in regard to its ability to antagonize the effect of 5-HT at such receptors. In the present study, we have analysed the effect of (+/-)pindolol on receptor-mediated G-protein activation by measuring guanylyl 5'-[gamma-[35S]thio]-triphosphate ([35S]GTPgammaS) binding onto tissue sections from the hippocampus and dorsal raphe nucleus from rat, guinea pig and human brain. In these regions, enriched in 5-HT1A receptors, (+/-)pindolol antagonized the stimulation of [35S]GTPgammaS binding induced by 5-HT in a concentration-dependent manner. We found that in both rat and human brain the calculated pEC50 values were higher in the dorsal raphe nucleus than in hippocampus. This suggests a higher potency of (+/-)pindolol at somatodendritic 5-HT1A receptors compared to post-synaptic 5-HT1A sites. In the absence of 5-HT, (+/-)pindolol (up to 10(-3) M) did not modify [35S]GTPgammaS binding, which remained at basal levels, indicating that, in this assay, (+/-)pindolol acts as a neutral antagonist rather than a partial agonist as it has been observed in other experimental models. The present data are relevant for the understanding of the neurobiological basis of pindolol acceleration of the action of SSRI antidepressants.
Publisher version (URL): http://journals.cambridge.org/download.php?file=/PNP/PNP7_01/S1461145703003924a.pdf&code=a7e5431b44cb3f0a00828a47df480146
URI: http://hdl.handle.net/10261/33045
DOI: 10.1017/S1461145703003924
ISSN: 1461-1457
E-ISSN: 1469-5111
Appears in Collections:(IIBB) Artículos
Files in This Item:
File Description SizeFormat 
download_An_autoradiographic.pdf179,12 kBAdobe PDFThumbnail
Show full item record

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.