title: Acute immobilization stress reduces (+/-)DOI-induced 5-HT2A receptor-mediated head shakes in rats.
abstract: Acute immobilization stress induced by taping four limbs, applying tail pinch stress and electric foot shock stress immediately reduced the frequency of head shakes induced by 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane ((+/-)DOI), a 5-HT2A/C agonist in rats. Immobilization stress due to the use of cylinder restraint and forced swimming did not affect 5-HT2A-mediated behavior. Acute immobilization stress did not affect [3H]ketanserin binding to the 5HT2A receptor in the prefrontal cortex and hippocampus. Presynaptic serotonergic lesions with 5,7-dihydroxytryptamine(5,7-DHT) did not affect the reduction in 5-HT2A-mediated behavior after acute immobilization stress. The decreases in head shake frequency after acute immobilization stress by taping were attenuated by pretreatment with diazepam (2.5 mg/kg IP): This attenuation was reversed by pretreatment with flumazenil (10 mg/kg IP). The reduction in (+/-)DOI-induced 5-HT2A-mediated behavior caused by stress may be related to a change in agonist affinity to the receptor or changes in other neurotransmitter systems or the effect of PI turnover.
authors.affiliation: Department of Neuropsychiatry, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamada
authors.forename: A
authors.initials: A
authors.lastname: Watanabe
authors.forename: M
authors.initials: M
authors.lastname: Nankai
authors.forename: M
authors.initials: M
authors.lastname: Toru
mesh_terms: D000818:Animals; D003975:Diazepam / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006257:Head / Q000502:physiology*; D007103:Immobilization; D008297:Male; D009043:Motor Activity; D051381:Rats; D017208:Rats, Wistar; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D013312:Stress, Physiological
chemical_list: D017366:Serotonin Receptor Agonists; D003975:Diazepam