Trillat AC, Malagié I, Mathé-Allainmat M, Anmela MC, Jacquot C, Langlois M, Gardier AM. Effects of WAY 100635 and (-)-5-Me-8-OH-DPAT, a novel 5-HT1A receptor antagonist, on 8-OH-DPAT responses.
Eur J Pharmacol 1998;
347:41-9. [PMID:
9650846 DOI:
10.1016/s0014-2999(98)00085-5]
[Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The neurochemical profile at both post and presynaptic 5-HT1A receptors of a novel 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) analog, 5-methyl-8-hydroxy-2-(di-n-propylamino)tetralin ¿(+/-)-5-Me-8-OH-DPAT¿ and its stereoisomers was determined and compared to that of the highly selective 5-HT1A receptor antagonist, N-[4-(2-methoxyphenyl)-1-piperazinyl]-N-(2-pyridinyl) cyclo-hexanecarboxamide (WAY 100635). We evaluated their effects on 8-OH-DPAT-induced decrease in cAMP production, on 8-OH-DPAT-induced decrease in rat ventral hippocampal extracellular 5-hydroxytryptamine (5-HText) levels and in body temperature in mice. Both (+/-)- and (-)-5-Me-8-OH-DPAT blocked the 8-OH-DPAT-induced inhibition of forskolin-stimulated cAMP production. Moreover, while having no significant effect when injected alone, (+/-)-, (-)-5-Me-8-OH-DPAT and WAY 100635 antagonized the 8-OH-DPAT-induced decrease in 5-HText in rats and hypothermia in mice. By contrast, the (+) isomer inhibited the cAMP synthesis and did not modify the 8-OH-DPAT response on 5-HText in ventral hippocampus. These data suggest that (+/-)-5-Me-8-OH-DPAT acts selectively, its activity residing in the (-) enantiomer, this latter compound acting similarly to WAY 100635 as a full, selective and silent 5-HT1A antagonist.
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