Thyrotropin releasing hormone potentiates the effects of imipramine on brain serotonergic system.
Daily administration of thyrotropin-releasing hormone (TRH) (20 mg/kg) for 10 days in 2 equally divided doses increased 5-hydroxytryptamine and/or 5-hydroxyindoleacetic acid levels in certain brain areas. Chronic imipramine treatment (10 mg/kg) for 10 days significantly decreased the levels of brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid. When TRH was administered concurrently with imipramine (10 mg/kg), this neuropeptide significantly potentiated the effects of imipramine on lowering of endogenous levels of 5-hydroxytryptamine (striatum, hypothalamus) and 5-hydroxyindoleacetic acid (striatum, midbrain, pons-medulla). Our data provide a possible neurochemical basis for the reported potentiation of tricyclic antidepressant action by TRH.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism; D007099:Imipramine / Q000494:pharmacology*; D008297:Male; D008526:Medulla Oblongata / Q000378:metabolism; D008636:Mesencephalon / Q000378:metabolism; D009928:Organ Specificity; D011149:Pons / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*
D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D013973:Thyrotropin-Releasing Hormone; D007099:Imipramine