Reduction in anxiety after ejaculation in the rat.

The anxiety levels, tested in the conditioned defensive burying behaviour paradigm, were analyzed after various phases of copulatory behaviour. No differences in anxiety were found between the group of animals without sexual activity and the group of animals tested after five intromissions of the first ejaculatory series. A decrease in anxiety, reflected as a reduction in the burying behaviour, was found in the group of animals tested during the first and the second postejaculatory intervals or after two intromissions from the second series of copulation. The possible involvement of the GABAergic system mediating the reduction in anxiety during these phases of copulation is discussed.