title: 5-HT2A and 5-HT2C serotonin receptors differentially modulate mouse sexual arousal and the hypothalamo-pituitary-testicular response to the presence of a female.
abstract: The role of 5-HT2A and 5-HT2C subtypes of serotonergic receptors in the control of sexual behavior and plasma testosterone regulation was studied in male CBA mice exposed to a sexually receptive female separated by a transparent partition. Introduction of the receptive female induced sexual motivation and arousal in males, as evidenced by a prolonged time spent at the partition, unsuccessful attempts to step across it and a significant increase in plasma testosterone levels. Administration of 5-HT2A receptor antagonists ketanserin (1.0 and 2.0 mg/kg i.p.) or cyproheptadine (1.0 and 2.0 mg/kg i.p.) diminished the behavioral components and prevented the hormonal components of male sexual arousal. Administration of the selective 5-HT2C antagonist RS 102221 (1.0 and 2.0 mg/kg) considerably increased the time spent by males at the partition (p < 0.001) and, at the dose of 2.0 mg/kg, increased plasma testosterone levels (p < 0.01). Administration of ritanserin - a nonselective 5-HT2A/2C antagonist and, to a smaller degree, 5-HT2B antagonist - at doses of 0.1 and 0.5 mg/kg did not significantly influence male behavior and the activating effect of the presence of a female on the hypothalamo-pituitary-testicular system, although it increased resting testosterone levels (p < 0.05). The present findings suggest that 5-HT2A/5-HT2C receptors may be involved in the neural control of male sexual motivation and arousal, presumably by exerting reciprocal facilitative (5-HT2A) or suppressive (5-HT2C) influences.
authors.affiliation: Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia. npopova@bionet.nsc.ru
authors.forename: Nina K
authors.initials: NK
authors.lastname: Popova
authors.forename: Tamara G
authors.initials: TG
authors.lastname: Amstislavskaya
mesh_terms: D000818:Animals; D003533:Cyproheptadine / Q000494:pharmacology; D005260:Female; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA; D044402:Receptor, Serotonin, 5-HT2A; D044405:Receptor, Serotonin, 5-HT2C; D011985:Receptors, Serotonin / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D012726:Sexual Behavior, Animal / Q000502:physiology*; D013141:Spiro Compounds / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013739:Testosterone / Q000097:blood
chemical_list: C107821:8-(5-(5-amino-2,4-dimethoxyphenyl)-5-oxopentyl)-1,3,8-triazaspiro(4.5)decane-2,4-dione; D044402:Receptor, Serotonin, 5-HT2A; D044405:Receptor, Serotonin, 5-HT2C; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D013141:Spiro Compounds; D013449:Sulfonamides; D003533:Cyproheptadine; D013739:Testosterone; D007650:Ketanserin