Anxiolytic-like effect of ejaculation under various sexual behavior conditions in the male rat

The purpose of the present study was to analyze the anxiety-like effect induced by ejaculation in male rats subjected to different sexual behavior conditions. The animal model of anxiety used was the conditioned defensive burying test. Results showed that experimental anxiety was reduced after one or six consecutive ejaculations. Six ejaculations did not induce a larger reduction in burying behavior than that produced by two, suggesting that this effect is not cumulative. This anxiolytic-like effect endured a short period (less than 24 h), and was not accompanied by a reduction in ambulatory behavior. The present results also showed a facilitating action of a previous ejaculation on the reduction in burying behavior induced by a second ejaculatory response. This potentiation occurred with an interval of 24 h between ejaculations. In sexually exhausted rats two populations are distinguished: one sexually unresponsive, and one achieving one ejaculation. Interestingly, in the ejaculatory population no reduction in burying behavior was observed, while in the unresponsive one a diminution in defensive burying was found. Data reveal differences in the anxiolytic-like properties of ejaculation between nonsatiated rats and the two populations of sexually exhausted animals. (C) 1999 Elsevier Science Inc. All Rights Reserved.