查看文章

The effect of an intracerebroventricular (i.c.v.) injection of the oxytocin antagonist, d(CH₂)₅Tyr(Me)-Orn⁸-vasotocin, on the copulatory behaviour of vigorous male rats in the presence of females in estrus was studied. The peptide (2.5, 25 and 50 ng, 15 min before mating tests) decreased the number of mounts and intromissions, and abolished ejaculation almost completely at all doses tested. The peptide failed to significantly influence motor activity at the doses used. The results support the hypothesis that central oxytocin playsiological role in the expression of copulatory behaviour.