Central administration of oxytocin differentially increases yawning, penile erections and scratching in high- (HY) and low-yawning (LY) sublines of Sprague-Dawley rats

摘要

Central administration of oxytocin has been shown to induce yawning, penile erection, grooming and scratching. Yawning and penile erections are due to activation of oxytocinergic neurons in the paraventricular nucleus of the hypothalamus. We selectively bred two sublines from Sprague-Dawley rats, one with a high-yawning frequency (HY) of 20 yawns/h, and one with a low-yawning (LY) frequency of 2 yawns/h. The aim of the current study was to analyze the behavioral effects of centrally-administered oxytocin [15 ng-10 mu g; intracerebroventricularly (i.c.v.)] on yawning, penile erections, grooming and scratching in adult male rats from both sublines.