title: Involvement of 5-hydroxytryptamine1A receptors in Delta9-tetrahydrocannabinol-induced catalepsy-like immobilization in mice.
abstract: The present study investigated the involvement of 5-hydroxytryptamine(1A) (5-HT(1A)) receptors in Delta(9)-tetrahydrocannabinol (THC)-induced catalepsy-like immobilization in mice. THC (10 mg/kg, i.p.) induced catalepsy-like immobilization but had no effect on motor coordination in the rota-rod test. The selective cannabinoid CB(1) receptor antagonist rimonabant (3 mg/kg, i.p.) completely antagonized THC-induced catalepsy-like immobilization. The 5-HT(1A)/5-HT(7) receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT; 0.3 and 1 mg/kg, i.p.) and 5-HT(1A) receptor partial agonist buspirone (0.06 and 0.1 mg/kg, i.p.) inhibited this THC-induced catalepsy-like immobilization. Moreover, the selective 5-HT(1A) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohezane carboxamide dihydrochloride (WAY100635; 0.3 or 1 mg/kg, i.p.) reversed the inhibition of THC-induced catalepsy-like immobilization by 8-OH-DPAT (1 mg/kg) or buspirone (0.06 mg/kg). In contrast, the selective 5-HT(7) receptor antagonist (R)-3-[2-[2-(4-methylpiperidin-1-yl)ethyl]pyrrolidine-1-sulfonyl]phenol hydrochloride (SB269970) had no effect on this inhibitory effect of 8-OH-DPAT. On the other hand, WAY100635 (0.3 and 1 mg/kg, i.p.) enhanced the catalepsy-like immobilization induced by THC (6 mg/kg, i.p.). These findings suggest that the 5-HT(1A) receptors are involved in THC-induced catalepsy-like immobilization.
authors.affiliation: Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka, University, 8-19-1, Nanakuma, Fukuoka 814-0180, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Egashira
authors.forename: Tomomi
authors.initials: T
authors.lastname: Matsuda
authors.forename: Emi
authors.initials: E
authors.lastname: Koushi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Mishima
authors.forename: Katsunori
authors.initials: K
authors.lastname: Iwasaki
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Shoyama
authors.forename: Michihiro
authors.initials: M
authors.lastname: Fujiwara
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D002065:Buspirone / Q000494:pharmacology; D002375:Catalepsy / Q000139:chemically induced* / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D013759:Dronabinol / Q000494:pharmacology*; D006213:Hallucinogens / Q000494:pharmacology*; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D004856:Postural Balance / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D044282:Receptor, Serotonin, 5-HT1A / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology
chemical_list: D006213:Hallucinogens; D010636:Phenols; D010879:Piperazines; D011725:Pyridines; C404922:SB 269970; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D013449:Sulfonamides; D044282:Receptor, Serotonin, 5-HT1A; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D013759:Dronabinol; D002065:Buspirone