These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Differential effect of gepirone on presynaptic and postsynaptic serotonin receptors: single-cell recording studies.
    Author: Blier P, de Montigny C.
    Journal: J Clin Psychopharmacol; 1990 Jun; 10(3 Suppl):13S-20S. PubMed ID: 1973935.
    Abstract:
    The sustained administration of the serotonin (5-hydroxytryptamine1A, 5-HT1A) agonist gepirone (15 mg/kg/day subcutaneously) in the rat produced an initial decrease of the firing activity of dorsal raphe 5-HT neurons, which was followed by a progressive recovery to normal after 14 days of treatment. At this point, the somatodendritic 5-HT1A autoreceptor had desensitized, as indicated by the reduced effectiveness of intravenous lysergic acid diethylamide (LSD) and of microiontophoretic applications of 5-HT, LSD, 8-hydroxy-2-(N,N-propylamino) tetralin (8-OH-DPAT), and gepirone, but not of gamma-aminobutyric acid in depressing the firing activity of 5-HT neurons. In contrast, the responsiveness of postsynaptic dorsal hippocampus pyramidal neurons to 5-HT, 8-OH-DPAT, and gepirone was not altered by the 14-day gepirone treatment. In an attempt to unravel the differential effect of sustained gepirone administration on presynaptic and postsynaptic 5-HT1A receptors, the properties of gepirone at these two receptors were assessed. The concurrent microiontophoretic application of gepirone readily blocked the effect of 5-HT on dorsal hippocampus pyramidal neurons, but not on dorsal raphe 5-HT neurons, thus indicating that gepirone is a partial agonist at postsynaptic 5-HT1A receptors and a full agonist at somatodendritic 5-HT1A receptors. It is proposed that gepirone, being a partial agonist at postsynaptic 5-HT1A receptors, fails to desensitize them; whereas, because of its full agonistic activity at the somatodendritic 5-HT1A receptor, it desensitizes this autoreceptor with long-term administration.(ABSTRACT TRUNCATED AT 250 WORDS)
    [Abstract] [Full Text] [Related] [New Search]