PMID: 8945740Nov 1, 1996Paper

The alpha 2-adrenoceptor antagonist idazoxan is an agonist at 5-HT1A autoreceptors modulating serotonin synthesis in the rat brain in vivo

Neuroscience Letters
J LladóJ A García-Sevilla

Abstract

The in vivo effects of the alpha 2-adrenoceptor idazoxan, rauwolscine and phentolamine on alpha 2-auto/heteroreceptors and 5-HT1A autoreceptors modulating the synthesis of dopa/noradrenaline and 5-HTP/serotonin were assessed in rats, using the accumulation of dopa and 5-HTP after decarboxylase inhibition as a measure of the rate of tyrosine and tryptophan hydroxylation. The acute administration of idazoxan (0.1-40 mg/kg) induced a pronounced dose-dependent increase in the synthesis of dopa in the cerebral cortex (22-86%) and hippocampus (8-80%), as a consequence of the powerful blockade of alpha 2-autoreceptors. However, idazoxan did not increase the synthesis of 5-HTP in these brain regions, as it would have been expected by the concurrent blockade of alpha 2-heteroreceptors on serotonergic terminals. Instead, idazoxan decreased the synthesis of 5-HTP in the cerebral cortex (13-33%) and hippocampus (25-48%), suggesting that these inhibitory effects were mediated through activation of 5-HT1A autoreceptors. Similar results were obtained for rauwolscine. Pre-treatment of rats with the selective 5-HT1A receptor antagonist WAY100135 (10 mg/kg) fully antagonized the inhibitory effects of idazoxan (10 mg/kg) on 5-HTP synthesis, but i...Continue Reading

References

May 25, 1991·European Journal of Pharmacology·H De VosG Vauquelin
Jun 25, 1991·European Journal of Pharmacology·R B McCallK A King
Mar 1, 1983·British Journal of Pharmacology·J C DoxeyC F Smith
Jun 24, 1993·European Journal of Pharmacology·A FletcherY Reilly

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Citations

Apr 5, 2000·European Journal of Pharmacology·C PolidoriM Massi
Aug 27, 1997·European Journal of Pharmacology·M C Wolff, J D Leander
Jul 3, 1998·European Journal of Pharmacology·A HaapalinnaR Lammintausta
Apr 29, 1998·British Journal of Pharmacology·J Ogilvie, R W Clarke
Jul 8, 2000·Neuropharmacology·R W ClarkeJ Ogilvie
Jun 18, 2002·European Journal of Pharmacology·Begoña Fernández-Pastor, J Javier Meana
Nov 30, 2011·Progress in Neuro-psychopharmacology & Biological Psychiatry·Raquel TonelloMaribel Antonello Rubin
Mar 20, 2003·Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology·Roberto W InvernizziRosario Samanin

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