Proceedings of The Physiological Society

Physiology 2016 (Dublin, Ireland) (2016) Proc Physiol Soc 37, PCA259

Poster Communications

Kisspeptin in the medial amygdala and sexual behaviour in male rats

R. Gresham1, D. A. Adekunbi1, S. Li1, M. Hu1, X. Li1, K. O'Byrne1

1. Women's Health Division, King's College London, London, United Kingdom.

Kisspeptin (Kiss1) plays an important modulatory role in sexual function. Mice that have had the kisspeptin receptor (Kiss1r) knocked out display no sexual behaviour. Recently Kiss1 and Kiss1r have been discovered in the posterodorsal subnucleus of the medial amygdala (MePD) [1], however the role of kisspeptin in this region remains unclear. Given that the medial amygdala is a vital brain region involved in sexual behavior, we hypothesized that Kiss1 in the MePD may have an influence on male sexual behaviour. Adult male Sprague Dawley rats (200-225g) were anaesthetized with ketamine hydrochloride USP (100 mg/kg) and Rompun (10 mg/kg) and positioned in a stereotaxic frame for chronic bilateral cannulation of the MePD [2]. After 3 days of recovery, ex-copula behavioral tests were performed. Ex-copula erections were scored by the emergence of the glans penis from the penile sheath and intensive penile grooming [3] during a 30 min period following infusion of kisspeptin (Kp) -10, kiss1r antagonist (Kp-234) or artificial cerebrospinal fluid (aCSF) into the MePD or lateral cerebroventricle. Correct cannula placement in the MePD was confirmed by microscopic inspection of 30 µm brain sections at the end of the study. Only data from animals with correct cannula placement were analyzed. Values are expressed as mean±S.E.M., and compared by ANOVA. Intra-MePD infusion of 1 nmol Kp-10 caused a significant increase in the number of ex-copula erections compared with aCSF in the 30 min post-treatment period (1.17±0.12, n=12 vs 0.17±0.07, n=5 respectively, P<0.05). These erections were attenuated by Kiss1r antagonist (Kp-234; 5 nmol). (Kp-10; 1.17±0.12, n=12, Kp-234; 0.25±0.06, n=3, P<0.05). There were no observed erections following intra-cerebroventricular injection of Kp-10 (1 or 5 nmol). These results indicate that kiss1 may play a facilitatory role on sexual arousal by acting as an erectogenic stimulus in the MePD. We conclude that Kiss1 has a role in male sexual behaviour, which is specific to the MePD.

Where applicable, experiments conform with Society ethical requirements