title: Cannabinoid receptor antagonism increases female sexual motivation.
abstract: The current experiments examined whether treatment with a CB1 antagonist/inverse agonist (AM251) affects sexual motivation, proceptivity, and receptivity in female rats. In experiment #1, 92 Long-Evans rats were tested for their socio-sexual motivation via a runway methodology. Motivation to approach and maintain close proximity to an empty goalbox, a female, and a male target was assessed following hormonal and drug treatment. Hormone treatments were: oil vehicle, 10 microg estradiol, and 10 microg estradiol+500 microg progesterone. Drug doses were 0, 2, and 4 mg/kg AM251 (IP, 60 min prior to testing). In experiment #2, 32 female subjects were tested for receptivity and proceptivity in a paced mating chamber. Subjects were given either a high (10 microg estradiol+500 microg progesterone) or low dose of hormones (2 microg estradiol+250 microg progesterone), and either vehicle or 2 mg/kg AM251. AM251 significantly increased sexual motivation for a male target in the runway in females primed with both estradiol and progesterone. AM251 also enhanced lordosis (in low hormone females) and increased hop-darts. These findings suggest that endocannabinoids tonically inhibit estrous behaviors. Cannabinoid antagonists could serve as new treatment option for women suffering from abnormally low libido.
authors.affiliation: Department of Psychology, Skidmore College, Saratoga Springs, NY 12866, USA. hlopez@skidmmore.edu
authors.forename: Hassan H
authors.initials: HH
authors.lastname: López
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Webb
authors.forename: Sean
authors.initials: S
authors.lastname: Nash
mesh_terms: D000818:Animals; D063387:Cannabinoid Receptor Antagonists; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D009042:Motivation; D009043:Motor Activity / Q000187:drug effects; D010052:Ovariectomy; D010880:Piperidines / Q000494:pharmacology*; D011187:Posture; D011374:Progesterone / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology*; D051381:Rats; D020318:Rats, Long-Evans; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D013268:Stimulation, Chemical
chemical_list: D063387:Cannabinoid Receptor Antagonists; D010880:Piperidines; D011720:Pyrazoles; C103505:AM 251; D011374:Progesterone; D004958:Estradiol