DSpace Repository

The effect of the selective 5-HT1A agonists alnespirone (S-20499) and 8-OH-DPAT on extracellular 5-hydroxytryptamine in different regions of rat brain

Show simple item record

dc.creator Casanovas, Josep M.
dc.creator Lesourd, Monique
dc.creator Artigas, Francesc
dc.date 2008-02-18T18:27:14Z
dc.date 2008-02-18T18:27:14Z
dc.date 1997-10
dc.date.accessioned 2017-01-31T01:00:11Z
dc.date.available 2017-01-31T01:00:11Z
dc.identifier British Journal of Pharmacology 122(4): 733–741 (1997)
dc.identifier 0007-1188
dc.identifier http://hdl.handle.net/10261/2973
dc.identifier 10.1038/sj.bjp.0701420
dc.identifier.uri http://dspace.mediu.edu.my:8181/xmlui/handle/10261/2973
dc.description 1. We have examined the effects of the systemic administration of the selective 5-HT1A agonist alnespirone (S-20499) on in vivo 5-hydroxytryptamine (5-HT) release in the dorsal raphe nucleus, the median raphe nucleus and four forebrain areas innervated differentially by both (dorsal striatum, frontal cortex, ventral hippocampus and dorsal hippocampus).
dc.description 2. Alnespirone (0.1–3mgkg−1, s.c.) dose-dependently reduced extracellular 5-HT in the six areas examined. In forebrain, the maximal reductions occurred in striatum and frontal cortex (maximal reduction to 23 and 29% of baseline, respectively). Those in dorsal and ventral hippocampus were more moderate (to ca 65% of baseline). In contrast, the decrease in 5-HT elicited in the median raphe nucleus was more marked than that in the dorsal raphe nucleus (to ca 30 and 60% of baseline, respectively). The selective 5-HT1A antagonist WAY-100635 (0.5mgkg−1, s.c.) prevented the decrease in 5-HT induced by alnespirone (0.3mgkg−1, s.c.) in frontal cortex.
dc.description 3. 8-OH-DPAT (0.025, 0.1 and 0.3mgkg−1, s.c.) also reduced extracellular 5-HT in a regionally-selective manner (e.g., to 32% of baseline in striatum and to 69% in dorsal hippocampus at 0.1mgkg−1, s.c.). In midbrain, 8-OH-DPAT reduced the dialysate 5-HT slightly more in the median than in the dorsal raphe nucleus at all doses examined.
dc.description 4. Doses of both compounds close to their respective ED50 values (0.3mgkg−1 alnespirone, 0.025mgkg−1 8-OH-DPAT) reduced 5-HT to a comparable extent in all regions examined. However, the reductions attained at higher doses were more pronounced for 8-OH-DPAT.
dc.description 5. These data show that the reduction of 5-HT release elicited by alnespirone and 8-OH-DPAT is more important in forebrain areas innervated by 5-hydroxytryptaminergic neurones of the dorsal raphe nucleus. This regional selectivity seems unlikely to be accounted for by differences in the sensitivity of 5-HT1A autoreceptors controlling 5-HT release, given the dissimilar effects of these two 5-HT1A agonists in regions rich in cell bodies and nerve terminals. This suggests the presence of complex mechanisms of control of 5-HT release by 5-HT1A receptors.
dc.description This work was supported by grants from the Institut de Recherches Internationales Servier and Fondo de Investigación Sanitaria (FIS 95/266).
dc.description Peer reviewed
dc.format 394539 bytes
dc.format application/pdf
dc.language eng
dc.publisher British Pharmacological Society
dc.relation http://dx.doi.org/10.1038/sj.bjp.0701420
dc.rights openAccess
dc.subject 5-Hydroxytryptamine (5-HT) release
dc.subject 5-Hydroxytryptamine1A agonists
dc.subject Antidepressants
dc.subject Dorsal raphe nucleus
dc.subject Dorsal striatum
dc.subject Hippocampus
dc.subject Median raphe nucleus
dc.subject Microdialysis
dc.title The effect of the selective 5-HT1A agonists alnespirone (S-20499) and 8-OH-DPAT on extracellular 5-hydroxytryptamine in different regions of rat brain
dc.type Artículo


Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record

Search DSpace


Advanced Search

Browse

My Account