title: Discriminative stimulus- and open-field effects of the enantiomers of 11-hydroxy-delta-8-tetrahydrocannabinol in pigeons and gerbils.
abstract: The cannabimimetic activity of the two enantiomers of 11-hydroxy-delta-8-tetrahydrocannabinol (11-OH-delta-8-THC) was evaluated in pigeons trained to discriminate between the presence and absence of (-)-delta-9-tetrahydrocannabinol [(-)-delta-9-THC]. (-)-11-OH-Delta-8-THC exhibited cannabimimetic activity with a potency (ED50, 0.17 mg/kg) similar to that of delta-9-THC. The duration of action for (-)-11-OH-delta-8-THC was shorter than that observed for delta-9-THC. No cannabimimetic activity was seen after administrations of (+)-11-OH-delta-8-THC, indicating enantiomeric selectivity for the discriminable effects. A dose-related decrease in response rate occurred with (-)-11-OH-delta-8-THC, but not with (+)-11-OH-delta-8-THC; the latter compound produced an increase in responding at 3 mg/kg. Open-field behavior in Mongolian gerbils indicated marked suppression of rearing (vertical activity) after treatments with (-)-delta-9-THC and (-)-11-OH-delta-8-THC; this did not occur after (+)-11-OH-delta-8-THC. The results support the notion of cannabimimetic enantiospecificity.
authors.affiliation: Department of Psychology, Faculty of Social Sciences, University of Uppsala, Sweden.
authors.forename: T U
authors.initials: TU
authors.lastname: Järbe
authors.forename: R
authors.initials: R
authors.lastname: Mechoulam
authors.forename: J
authors.initials: J
authors.lastname: Zahalka
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002186:Cannabinoids / Q000494:pharmacology; D010856:Columbidae; D004193:Discrimination Learning / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005849:Gerbillinae; D008297:Male; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D002186:Cannabinoids; C020367:11-hydroxy-delta(8)-tetrahydrocannabinol; D013759:Dronabinol