title: The Influence of hyperactivity of the hypothalamic-pituitary-adrenal axis and hyperglycemia on the 5-HT2A receptor-mediated wet-dog shake responses in rats.
abstract: Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis induces hyperglycemia and serotonin (5-HT)2A receptor supersensitivity. In the present study, to investigate the effect of hyperglycemia on the function of 5-HT2A receptors, we compared the 5-HT2A receptor-mediated wet-dog shake responses in rats treated with adrenocorticotropic hormone (ACTH), dexamethasone and streptozotocin. ACTH (100 ug/rat per day, s.c.), dexamethasone (1 mg/kg per day, s.c.) and streptozotocin (60 mg/kg, i.p.) produced significant hyperglycemia at 14 days after the start of these treatments, and the hyperglycemia was most pronounced in the streptozotocin-treated rats. The wet-dog shake responses induced by (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a 5-HT2A receptor agonist, were significantly enhanced at 14 days after repeated treatment with ACTH and dexamethasone. However, streptozotocin-induced diabetes had no effect on the wet-dog shake responses. The results of the present study suggest that hyperglycemia is not strongly associated with the enhanced susceptibility of 5-HT2A receptors under the condition of hyperactivity of the HPA axis.
authors.affiliation: Department of Clinical Pharmacology and Pharmacy, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Umeda
authors.forename: Manabu
authors.initials: M
authors.lastname: Amano
authors.forename: Katsuya
authors.initials: K
authors.lastname: Suemaru
authors.forename: Takumi
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Gomita
authors.forename: Hiromu
authors.initials: H
authors.lastname: Kawasaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Araki
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D003907:Dexamethasone / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D005938:Glucocorticoids / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology; D006943:Hyperglycemia / Q000503:physiopathology*; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D044402:Receptor, Serotonin, 5-HT2A / Q000378:metabolism*; D013239:Stereotyped Behavior / Q000187:drug effects / Q000502:physiology; D013311:Streptozocin / Q000494:pharmacology
chemical_list: D005938:Glucocorticoids; D006728:Hormones; D044402:Receptor, Serotonin, 5-HT2A; D013311:Streptozocin; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone