Aldosterone blocks the response to corticosterone in the raphe-hippocampal serotonin system.
The accumulation of serotonin induced by the monoamino oxidase inhibitor pargyline was used as an index for 5-HT turnover in the dorsal hippocampus and raphe area. A low dose of corticosterone administered s.c. immediately after adrenalectomy significantly increased serotonin turnover in both regions over the subsequent 1 h interval. The same dose of aldosterone was ineffective, but pretreatment with aldosterone blocked the serotonin response to corticosterone in the acutely adrenalectomized rat. [3H]Corticosterone administered to adrenalectomized rats was not retained by cell nuclei of the raphe area in a limited capacity manner as occurred in the hippocampus. Pretreatment with aldosterone blocked the uptake of [3H]corticosterone in hippocampal cell nuclei. It is concluded that corticosterone triggers a serotonin response and that the specificity of the corticosterone action suggests involvement of the steroid receptor system located postsynaptically to the raphe-hippocampal serotonin projection.
D000450:Aldosterone / Q000494:pharmacology*; D000818:Animals; D001933:Brain Stem / Q000187:drug effects*; D003345:Corticosterone / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D011903:Raphe Nuclei / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism / Q000502:physiology*
D012701:Serotonin; D000450:Aldosterone; D003345:Corticosterone