Female Wistar rats tested during late proestrus or during pregnancy and ovariectomized rats tested after receiving progesterone or allopregnanolone displayed reduced conflict behavior.
In a conflict test based on the rat's choice between an immediate punished reinforcer or a delayed nonpunished reinforcer, anxiolytic drugs increase the number of immediate punished reinforcers. In this study, two hypotheses were tested: first, during late proestrus or during midpregnancy, female rats will display an elevated amount of immediate punished reinforcers; second, ovariectomized rats will display an elevated amount of immediate punished reinforcers when they receive anxiolytic doses of neurosteroids. Thus, female rats (n = 15) were tested repeatedly during late proestrus, diestrus, and pregnancy in the aforementioned conflict task. They displayed an elevated amount of immediate punished reinforcers during late proestrus (P < .05) and during the 14th (P < .05) and 17th (P < .05) days of pregnancy compared to diestrus or 3rd, 7th, or 20th days of pregnancy. Likewise, ovariectomized rats (n = 90) displayed an elevated amount of immediate punished reinforcers compared to control rats only when they received anxiolytic doses of progesterone (1.0-2.0 mg/kg, P < .05) or allopregnanolone (1.0-2.0 mg/kg, P < .05). In conclusion, female rats displayed reduced conflict behavior during late proestrus and pregnancy, or after received anxiolytic doses of neurosteroids.
D000818:Animals; D002755:Choice Behavior / Q000187:drug effects / Q000502:physiology; D003220:Conflict, Psychological; D004305:Dose-Response Relationship, Drug; D005260:Female; D010052:Ovariectomy; D011247:Pregnancy; D011280:Pregnanolone / Q000494:pharmacology*; D011359:Proestrus / Q000187:drug effects* / Q000502:physiology; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D011374:Progesterone; D011280:Pregnanolone