Park, D.S.*; Propper, C. R.: Purification and Action of a Repelling Pheromone from Male Red-spotted Newts

Male red-spotted newts, Notopthalmus viridescens, interacting with females release repelling pheromones that function to repel conspecific males. It has suggested that the repelling pheromones may conserve both the courting and approaching (towards a courting group) males’ reproductive fitness by controlling the sex ratio within the courting arena. Using behavioral bio-assays, column-chromatography, and SDS-PAGE, we have begun to purify the repelling pheromone. Also, the pathway for the action of the repelling pheromone in male olfactory organ was investigated using an electro-olfacto-gram (EOG) analysis. We found that 1) the repelling pheromone is produced from male cloacal glands, 2) the repelling pheromone is protein of approximately 37 kda, and 3) the repelling pheromone induces higher olfactory response from the vomeronasal system than the main olfactory organ of male newts. These results suggest that the proteinacious repelling phromone induces repelling responses from conspecific males via the vomeronasal organ. The Council of Tobacco Research, USA (#4601811) to C.R.P supported this work.