Meeting Abstract

P2.98  Tuesday, Jan. 5  Effects of pheromone treatment on gonadotropin-releasing hormone and arginine vasotocin neurons in the brain of a terrestrial salamander WACK, Corina L.*; WOODLEY, Sarah K.; Duquesne University; Duquesne University wackc@duq.edu

Gonadotropin-releasing hormone (GnRH) and arginine vasotocin (AVT) are important neuromodulators of reproductive and social behaviors. Both GnRH and AVT neurons may be modulated by pheromones to influence expression of behavior. We tested the hypothesis that pheromones would affect the number of GnRH and AVT neurons in the red-legged salamander (Plethodon shermani), an emerging non-mammalian model for studies in chemosensory communication. A courtship pheromone from the mental gland of the male red-legged salamander increases female receptivity, thus we predicted that this pheromone would increase the number of GnRH and AVT neurons in females compared to males. We applied male courtship pheromone or vehicle control to the nares of male (reproductive) and female (reproductive and non-reproductive) red-legged salamanders. Females that received pheromone had more GnRH neurons in the rostral telencephalon than control females that received the vehicle. Females overall had significantly more GnRH neurons in the caudal telencephalon than males. There was no effect of pheromones on the number of AVT neurons, but females had significantly more AVT neurons in the dorsal pallium than males. Additionally, reproductive males and females had more AVT neurons in the posterior preoptic area than non-reproductive females. These results suggest that male courtship pheromones influence the GnRH system but not the AVT system in red-legged salamanders.