title: 7α-Hydroxypregnenolone regulates diurnal changes in sexual behavior of male quail.
abstract: In the Japanese quail, 7α-hydroxypregnenolone, a previously undescribed avian neurosteroid, is actively produced in the brain. 7α-Hydroxypregnenolone acts as a novel neuronal activator to stimulate locomotor activity of quail. Therefore, in this study, we determined whether 7α-hydroxypregnenolone changes the expression of sexual behavior in Japanese quail. We first measured diurnal changes in sexual behavior of male quail exposed to a long-day photoperiod. We found that sexual behavior of male quail was high in the morning when endogenous 7α-hydroxypregnenolone level is high. Subsequently, we centrally administered 7α-hydroxypregnenolone in the evening when endogenous 7α-hydroxypregnenolone level is low. In the 30 min after intracerebroventricular (ICV) injection, 7α-hydroxypregnenolone dose dependently increased the frequency of sexual behavior of male quail. However, 7β-hydroxypregnenolone, a stereoisomer of 7α-hydroxypregnenolone, did not effect on the frequency of sexual behavior of male quail. In addition, to confirm the action of 7α-hydroxypregnenolone on sexual behavior, male birds received an ICV injection of ketoconazole, an inhibitor of cytochrome P450s, and behavioral experiments were performed in the morning. Ketoconazole significantly decreased the frequency of sexual behavior of male quail, whereas administration of 7α-hydroxypregnenolone to ketoconazole-treated males increased the frequency of their sexual behavior. These results indicate that 7α-hydroxypregnenolone regulates diurnal changes in sexual behavior of male quail.
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ogura
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan. Electronic address: shogo.haraguchi@gmail.com.
authors.forename: Shogo
authors.initials: S
authors.lastname: Haraguchi
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan.
authors.forename: Koki
authors.initials: K
authors.lastname: Nagino
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Ishikawa
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Fukahori
authors.affiliation: Laboratory of Integrative Brain Sciences, Department of Biology, Waseda University, and Center for Medical Life Science of Waseda University, Tokyo 162-8480, Japan. Electronic address: k-tsutsui@waseda.jp.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tsutsui
mesh_terms: D006907:17-alpha-Hydroxypregnenolone / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000378:metabolism*; D002940:Circadian Rhythm / Q000187:drug effects*; D003370:Coturnix; D008297:Male; D017440:Photoperiod; D012725:Sexual Behavior / Q000187:drug effects*
chemical_list: D006907:17-alpha-Hydroxypregnenolone
keywords: 7α-Hydroxypregnenolone; Neurosteroids; Quail; Sexual behavior