2,5-Dimethoxy-4-iodoamphetamine (DOI) inhibits Delta9-tetrahydrocannabinol-induced catalepsy-like immobilization in mice.
The effect of the serotonin 5-HT(2A/2C)-receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) on Delta(9)-tetrahydrocannabinol (THC)-induced catalepsy-like immobilization was studied in mice. DOI (0.3 and 1 mg/kg, i.p.) significantly inhibited the catalepsy-like immobilization induced by THC (10 mg/kg, i.p.). In contrast, the selective 5-HT(2C)-receptor agonist 8,9-dichloro-2,3,4,4a-tetrahydro-1H-pyrazino[1,2-a]quinoxalin-5(6H)-one (WAY 161503) had no effect on this catalepsy-like immobilization. Moreover, the 5-HT(2A)-receptor antagonist ketanserin (0.3 mg/kg, i.p.) reversed the inhibition of THC-induced catalepsy-like immobilization caused by DOI (1 mg/kg), whereas the selective 5-HT(2C)-receptor antagonist 6-chloro-2,3-dihydro-5-methyl-N-[6-(2-methyl-3-pyridinyl)oxyl]-3-pyridinyl]-1H-indole-1-carboxyamide (SB 242084) did not affect this inhibitory effect of DOI. On the other hand, ketanserin (0.3 and 1 mg/kg, i.p.) enhanced the catalepsy-like immobilization induced by THC (6 mg/kg, i.p.). Thus, on the basis of these results, it appears that 5-HT(2A)-receptor mechanisms might be responsible for the inhibitory effect of DOI on THC-induced catalepsy-like immobilization.
Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan.
Nobuaki
N
Egashira
Emi
E
Koushi
Kenichi
K
Mishima
Katsunori
K
Iwasaki
Ryozo
R
Oishi
Michihiro
M
Fujiwara
D000631:Aminopyridines / Q000008:administration & dosage / Q000494:pharmacology; D000662:Amphetamines / Q000008:administration & dosage / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D021461:Animals, Outbred Strains; D001522:Behavior, Animal / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D013759:Dronabinol / Q000633:toxicity*; D046352:Freezing Reaction, Cataleptic / Q000187:drug effects*; D007211:Indoles / Q000008:administration & dosage / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D007650:Ketanserin / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D051379:Mice; D011719:Pyrazines / Q000008:administration & dosage / Q000494:pharmacology; D011810:Quinoxalines / Q000008:administration & dosage / Q000494:pharmacology; D058826:Serotonin 5-HT2 Receptor Agonists; D017366:Serotonin Receptor Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
C107820:6-chloro-5-methyl-1-((2-(2-methylpyrid-3-yloxy)pyrid-5-yl)carbamoyl)indoline; C502777:8,9-dichloro-2,3,4,4a-tetrahydro-1H-pyrazino(1,2-a)quinoxalin-5(6H)-one; D000631:Aminopyridines; D000662:Amphetamines; D007211:Indoles; D011719:Pyrazines; D011810:Quinoxalines; D058826:Serotonin 5-HT2 Receptor Agonists; D017366:Serotonin Receptor Agonists; D013759:Dronabinol; D007650:Ketanserin; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine