title: Identification of an olfactory signal molecule that activates the central regulator of reproduction in goats.
abstract: Pheromone signals regulate conspecific behavior and physiology [1]. Releaser pheromones induce specific behavior by exerting acute effects on the neuronal response, whereas primer pheromones induce physiological changes with long-lasting effects by changing the neuroendocrine status of the recipients. In mammals, although several types of releaser pheromones have been identified [2-5], the identities of primer pheromones, as well as their mechanisms of action, remain largely unknown [6]. In sheep and goats, the seasonally anestrous endocrine state of females is changed to the estrous state upon exposure to male scents [7, 8]. This so-called "male effect" is one of the most conspicuous primer pheromone effects in mammals [9, 10]. In this study, we have identified an olfactory signal molecule that activates the central regulator of reproduction, the gonadotropin-releasing hormone (GnRH) pulse generator, in goats. Using gas chromatography-mass spectrometry to analyze male goat headspace volatiles, we identified several ethyl-branched aldehydes and ketones. We electrophysiologically demonstrated that one of these compounds, 4-ethyloctanal, activates the GnRH pulse generator in female goats. This is the first report of an olfactory molecule that has been shown to activate the central reproductive axis, and this discovery will provide a new direction for primer pheromone research.
authors.affiliation: Laboratory of Veterinary Ethology, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Murata
authors.affiliation: Technical Research Institute, T. Hasegawa Co., Ltd., 29-7 Kariyado, Nakahara-ku, Kawasaki-shi, Kanagawa 211-0022, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Tamogami
authors.affiliation: Technical Research Institute, T. Hasegawa Co., Ltd., 29-7 Kariyado, Nakahara-ku, Kawasaki-shi, Kanagawa 211-0022, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Itou
authors.affiliation: Technical Research Institute, T. Hasegawa Co., Ltd., 29-7 Kariyado, Nakahara-ku, Kawasaki-shi, Kanagawa 211-0022, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Ohkubo
authors.affiliation: Animal Physiology Research Unit, National Institute of Agrobiological Sciences, 2 Ikenodai, Tsukuba, Ibaraki 305-0901, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Wakabayashi
authors.affiliation: Laboratory of Organic Chemistry, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Animal Physiology Research Unit, National Institute of Agrobiological Sciences, 2 Ikenodai, Tsukuba, Ibaraki 305-0901, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Okamura
authors.affiliation: Laboratory of Veterinary Ethology, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. Electronic address: aytake@mail.ecc.u-tokyo.ac.jp.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Takeuchi
authors.affiliation: Laboratory of Veterinary Ethology, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Mori
mesh_terms: D000447:Aldehydes / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001681:Biological Assay; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006041:Goats / Q000502:physiology*; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology*; D007986:Luteinizing Hormone / Q000502:physiology; D008297:Male; D012098:Reproduction / Q000502:physiology*; D012724:Sex Attractants / Q000302:isolation & purification / Q000502:physiology*; D012903:Smell / Q000502:physiology
chemical_list: D000447:Aldehydes; D012724:Sex Attractants; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone