title: Effects of physical and psychological stress on 5-HT2A receptor-mediated wet-dog shake responses in streptozotocin-induced diabetic rats.
abstract: Several epidemiological and clinical studies have indicated that the prevalence of psychiatric disorders is higher in diabetic patients than in the general population. In the present studies, we examined the behavioral changes in streptozotocin-induced diabetic rats, and investigated the effects of physical and psychological stress on the hippocampal BDNF levels and on the serotonin 2A (5-HT(2A)) receptor-mediated wet-dog shake responses. The streptozotocin (60 mg/kg, i.p.)-induced diabetes had no significant effects on the immobility time in the forced swim test or on locomotor activity in the open-field test. Moreover, there was no significant difference in the wet-dog shake responses induced by DOI, a 5-HT(2A) receptor agonist, between nondiabetic and diabetic rats. Five-day exposure to physical (electric footshock) and psychological (non-footshock) stress had no significant effect on the hippocampal BDNF level in diabetic or nondiabetic rats. The 2 types of stress had no significant effect on the DOI-induced wet-dog shake responses in nondiabetic rats. In diabetic rats, the repeated exposure to physical stress markedly increased the DOI-induced wet-dog shake responses, but the repeated exposure to psychological stress had no effect. These results suggest that exposure to physical stress augmented the susceptibility to the wet-dog shake responses to 5-HT(2A) receptor stimulation in streptozotocin-induced diabetic rats.
authors.affiliation: Department of Clinical Pharmaceutical Science, Okayama University Graduate School of Natural Science and Technology, Okayama 700-8530, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Amano
authors.forename: Katsuya
authors.initials: K
authors.lastname: Suemaru
authors.forename: Ranji
authors.initials: R
authors.lastname: Cui
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Umeda
authors.forename: Bingjin
authors.initials: B
authors.lastname: Li
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: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D004195:Disease Models, Animal; D004558:Electric Stimulation; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D044402:Receptor, Serotonin, 5-HT2A / Q000502:physiology*; D013311:Streptozocin; D013315:Stress, Psychological / Q000150:complications / Q000503:physiopathology*
chemical_list: D044402:Receptor, Serotonin, 5-HT2A; D013311:Streptozocin