PT  - JOURNAL ARTICLE
AU  - A D Levy
AU  - Q A Li
AU  - J E Kerr
AU  - P A Rittenhouse
AU  - G Milonas
AU  - T M Cabrera
AU  - G Battaglia
AU  - M C Alvarez Sanz
AU  - L D Van de Kar
TI  - Cocaine-induced elevation of plasma adrenocorticotropin hormone and corticosterone is mediated by serotonergic neurons.
DP  - 1991 Nov 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 495--500
VI  - 259
IP  - 2
4099  - http://jpet.aspetjournals.org/content/259/2/495.short
4100  - http://jpet.aspetjournals.org/content/259/2/495.full
SO  - J Pharmacol Exp Ther1991 Nov 01; 259
AB  - We investigated the hypothesis that cocaine-induced elevations of plasma adrenocorticotropin hormone (ACTH) and corticosterone are mediated by brain serotonin (5-HT) neurons. Adult male rats were pretreated with the 5-HT depleting agent p-chlorophenylalanine, the 5-HT neurotoxin 5,7-dihydroxytryptamine, the partial 5-HT1A agonist 8-(2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl)-8- azaspirol[4,5]-decane-7,9-dione (BMY 7378) or the 5-HT1C/2 antagonist ritanserin. The effects of cocaine (2-15 mg/kg, i.p.) on plasma ACTH and corticosterone were then examined. Cocaine dose-dependently increased ACTH and corticosterone concentration. This increase was prevented by 5-HT depletion with PCPA and by destruction of 5-HT neurons with i.c.v. injections of 5,7-dihydroxytryptamine. The cocaine-induced elevation of ACTH and corticosterone was not significantly modified by administration of the partial 5-HT1A agonist BMY 7378, suggesting that 5-HT1A receptors probably do not mediate ACTH and corticosterone secretion. However, pretreatment with the 5-HT2/5-HT1C antagonist ritanserin virtually eliminated the cocaine-induced elevation of corticosterone. To determine whether these effects of cocaine are centrally mediated, conscious rats received cocaine injections into the cerebral ventricle through chronically implanted cannulas. Plasma ACTH concentrations were dose-dependently increased, whereas low doses (50 micrograms/kg, i.c.v.) produced a maximal increase in corticosterone concentration. These data indicate that the cocaine-induced stimulation of ACTH and corticosterone secretion is mediated by 5-HT neurons in brain, and furthermore, that 5-HT2 or 5-HT1C receptors are responsible for this effect.