Inhibition of the central hypotensive effect of clonidine by trazodone, a novel antidepressant.
Trazodone, a non-tricyclic drug with antidepressant properties, diminished the central hypotensive response to clonidine in a dose-dependent manner. Both drugs were infused into the left vertebral artery of chloralose-anaesthetized cats. Intravenously injected trazodone did not reduce the central hypotensive effect of clonidine. The antagonism probably occurs at the level of central alpha-adrenoreceptors in the brain stem, where clonidine is the alpha-agonist and trazodone the alpha-antagonist. Such an antagonism, already known for clonidine and the tricyclic drugs also holds for non-tricyclic antidepressants, provided that they possess alpha-adrenoreceptor-blocking activity.
D000818:Animals; D000928:Antidepressive Agents; D002415:Cats; D055598:Chemical Phenomena; D002621:Chemistry; D003000:Clonidine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D007269:Injections, Intra-Arterial; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D014196:Trazodone / Q000008:administration & dosage / Q000494:pharmacology*
D000928:Antidepressive Agents; D010879:Piperazines; D003000:Clonidine; D014196:Trazodone