Down-regulation of beta-adrenergic receptors following repeated injections of desmethylimipramine: permissive role of serotonergic axons.
The injection of desmethylimipramine (DMI) twice daily for 3 weeks reduced the density of beta-adrenergic receptor recognition sites located in crude synaptic membranes prepared from the cortex and hippocampus and attenuated the stimulation of the membrane-bound adenylate cyclase by isoproterenol. Both actions were abolished if prior to treatment with desmethylimipramine the serotonergic axons were destroyed by an intraventricular injection of 5,7-dihydroxytryptamine. These results show that the down-regulation of beta-adrenergic receptors elicited by repeated injections of desmethylimipramine occurs only if the serotonergic axons are intact.
D015116:5,7-Dihydroxytryptamine / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D000928:Antidepressive Agents; D001369:Axons / Q000502:physiology*; D002540:Cerebral Cortex / Q000378:metabolism; D003891:Desipramine / Q000494:pharmacology*; D006624:Hippocampus / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects* / Q000502:physiology; D012701:Serotonin / Q000502:physiology*
D000928:Antidepressive Agents; D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D015116:5,7-Dihydroxytryptamine; D012701:Serotonin; D000262:Adenylyl Cyclases; D007545:Isoproterenol; D003891:Desipramine