PMID- 10101737 OWN - NLM STAT- MEDLINE DCOM- 19990527 LR - 20190915 IS - 0306-4530 (Print) IS - 0306-4530 (Linking) VI - 24 IP - 3 DP - 1999 Apr TI - Alpha 2-adrenoreceptor subtypes regulate ACTH and beta-endorphin secretions during stress in the rat. PG - 333-43 AB - The effect of different alpha 2-adrenoreceptor subtype agonists and antagonists on adrenocorticotrop hormone (ACTH) and beta-endorphin release induced by ether stress was examined. Ether inhalation-induced ACTH and beta-endorphin increase was inhibited by i.c.v. administration of 30 micrograms but not 1 and 10 micrograms clonidine (alpha 2-adrenoreceptor agonist). I.c.v. oxymetazoline (alpha 2A-adrenoreceptor agonist; 1-10-30 micrograms) or the alpha 1-agonist methoxamine (100 micrograms/rat) failed to inhibit the stress-induced rise. Pretreatment with the alpha 1/alpha 2B.C-antagonist prazosin (0.5 mg/kg, i.p.) prevented the effect of clonidine on the ether stress, while the alpha 1/alpha 2A-antagonist WB-4101 (0.5 mg/kg, i.p.) was unable to counteract the inhibitory effect of clonidine. Prazosin alone had no effect on the ether-induced plasma ACTH and beta-endorphin elevation. These results suggest that noradrenaline in the central nervous system may inhibit the stress-induced hypothalamo-pituitary-axis and pituitary beta-endorphin activation via alpha 2B.C-adrenoceptor subtypes and prazosin may antagonize its effect on these receptors. FAU - Zelena, D AU - Zelena D AD - Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary. FAU - Kiem, D T AU - Kiem DT FAU - Barna, I AU - Barna I FAU - Makara, G B AU - Makara GB LA - eng PT - Journal Article PL - England TA - Psychoneuroendocrinology JT - Psychoneuroendocrinology JID - 7612148 RN - 0 (Adrenergic alpha-Agonists) RN - 0 (Adrenergic alpha-Antagonists) RN - 0 (Dioxanes) RN - 0 (Receptors, Adrenergic, alpha) RN - 0F5N573A2Y (Ether) RN - 60617-12-1 (beta-Endorphin) RN - 9002-60-2 (Adrenocorticotropic Hormone) RN - E9H51OIT2B ((2-(2',6'-dimethoxy)phenoxyethylamino)methylbenzo-1,4-dioxane) RN - HUQ1KC1YLI (Methoxamine) RN - MN3L5RMN02 (Clonidine) RN - XM03YJ541D (Prazosin) SB - IM MH - Adrenergic alpha-Agonists/pharmacology MH - Adrenergic alpha-Antagonists/pharmacology MH - Adrenocorticotropic Hormone/*metabolism MH - Animals MH - Clonidine/pharmacology MH - Dioxanes/pharmacology MH - Ether/pharmacology MH - Kinetics MH - Male MH - Methoxamine/pharmacology MH - Prazosin/pharmacology MH - Rats MH - Rats, Wistar MH - Receptors, Adrenergic, alpha/*physiology MH - Stress, Physiological/chemically induced/*physiopathology MH - beta-Endorphin/*metabolism EDAT- 1999/04/02 00:00 MHDA- 1999/04/02 00:01 CRDT- 1999/04/02 00:00 PHST- 1999/04/02 00:00 [pubmed] PHST- 1999/04/02 00:01 [medline] PHST- 1999/04/02 00:00 [entrez] AID - S0306-4530(98)00081-X [pii] AID - 10.1016/s0306-4530(98)00081-x [doi] PST - ppublish SO - Psychoneuroendocrinology. 1999 Apr;24(3):333-43. doi: 10.1016/s0306-4530(98)00081-x.