The effect of naloxone on sexual behavior in female rats depends on the site of injection.
Intraperitoneal injections of the opiate receptor antagonist naloxone (0.1, 1, 5 or 10 mg) had no effects on sexual behavior in ovariectomized female rats made either partially or fully receptive by injections of ovarian hormones. Intracerebroventricular (i.c.v.) injections of naloxone (10, 50 or 100 micrograms) had no effects on the behavior of partially receptive rats and in fully receptive rats an i.c.v. injection of a high dose of naloxone (100 micrograms) inhibited the behavior. Intrathecal (i.t.) injections of naloxone (50 or 100 micrograms) facilitated sexual behavior in partially receptive rats while i.t. injections of even very high doses of naloxone (500 micrograms) had no behavioral effects in fully receptive rats. Thus, the effects of naloxone on female sexual behavior depend on the site of injection.
D000818:Animals; D002490:Central Nervous System / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D009270:Naloxone / Q000494:pharmacology*; D010052:Ovariectomy; D011187:Posture; D011374:Progesterone / Q000494:pharmacology; D051381:Rats; D012726:Sexual Behavior, Animal / Q000187:drug effects*
D009270:Naloxone; D011374:Progesterone; D004958:Estradiol