title: Tilapia male urinary pheromone stimulates female reproductive axis.
abstract: Mozambique tilapia males congregate in leks where they establish dominance hierarchies and attract females to spawn in sandy pits. Dominant males store more urine than subordinates and the pattern of urination and the high sensitivity of females to male urine suggest chemical signalling via the urine. Here we show that pre-ovulated and post-spawn females when exposed to dominant male urine increased significantly, in less than 1h, the release rate of the maturation-inducing steroid 17,20β-dihydroxypregn-4-en-3-one which is maintained elevated for at least 6h. This indicates a pheromonal role for male urine in the synchronisation of spawning. Furthermore, we show that the lack of affinity of 17,20βP to sex steroid binding globulin explains, at least partly, its rapid release and lack of detection in the blood. Thus tilapia urine involvement in several communication processes confirms that cichlids have evolved a sophisticated chemical signalling system together with their complex visual, acoustic and behavioural displays.
authors: Centro de Ciências do Mar, CCMAR-CIMAR Laboratório Associado, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors: Mar
authors: M
authors: Huertas
authors: Centro de Ciências do Mar, CCMAR-CIMAR Laboratório Associado, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors: Olinda G
authors: OG
authors: Almeida
authors: Centro de Ciências do Mar, CCMAR-CIMAR Laboratório Associado, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors: Adelino V M
authors: AV
authors: Canário
authors: Centro de Ciências do Mar, CCMAR-CIMAR Laboratório Associado, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal. Electronic address: phubbard@ualg.pt.
authors: Peter C
authors: PC
authors: Hubbard
mesh_terms: D000818:Animals; D005260:Female; D006908:Hydroxyprogesterones / Q000378:metabolism*; D008297:Male; D010060:Ovulation / Q000502:physiology; D011863:Radioimmunoassay; D012098:Reproduction / Q000187:drug effects / Q000502:physiology*; D012724:Sex Attractants / Q000494:pharmacology* / Q000652:urine; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D012726:Sexual Behavior, Animal; D012741:Sexual Maturation / Q000502:physiology; D017210:Tilapia / Q000502:physiology / Q000652:urine*
chemical_list: D006908:Hydroxyprogesterones; D012724:Sex Attractants; D012738:Sex Hormone-Binding Globulin; C021012:17 alpha,20 beta-dihydroxypregn-4-en-3-one
keywords: 17,20β-Dihydroxypregn-4-en-3-one; Chemical communication; Cichlid; Pheromone; Reproduction; Sex steroid binding globulin; Steroid release