Possible subsensitization of alpha 2-adrenergic receptors by chronic monoamine oxidase inhibitor treatment in psychiatric patients.
Clonidine was administered to nine psychiatric patients before and after chronic treatment (3 to 4 weeks) with clorgyline, a selective monoamine oxidase type A inhibitor with antidepressant efficacy. The hypotensive response to clonidine, believed to be mediated by brain alpha 2-adrenergic receptors, was significantly attenuated by chronic but not acute (2 to 3 days) clorgyline treatment, with a time course similar to the onset of its clinical efficacy. This study supports the hypothesis that subsensitization of alpha 2-adrenergic receptors plays an important role in clorgyline's antidepressant effects and may constitute a key contribution to the mode of action of other antidepressant treatments as well.
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D001833:Body Temperature Regulation / Q000187:drug effects; D003000:Clonidine; D003010:Clorgyline / Q000627:therapeutic use*; D003866:Depressive Disorder / Q000188:drug therapy*; D004311:Double-Blind Method; D006801:Humans; D008875:Middle Aged; D009638:Norepinephrine / Q000378:metabolism; D011437:Propylamines / Q000627:therapeutic use*; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*
D011437:Propylamines; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D003010:Clorgyline; D003000:Clonidine; D009638:Norepinephrine