Number of preoptic GnRH-immunoreactive cells correlates with sexual phase in a protandrously hermaphroditic fish, the dusky anemonefish (Amphiprionmelanopus) |
| |
Authors: | U Elofsson S Winberg R C Francis |
| |
Institution: | Vertebrate Physiology and Behaviour Unit, Department of Limnology, Uppsala University, Norbyv?gen 20, S-752 36 Uppsala, Sweden, Tel.: +46-18 472615; Fax: +46-18 472609 e-mail: ulf.elofsson@limno.uu.se, SE Department of Animal Development and Genetics, Uppsala University, Norbyv?gen 18A, S-752 36 Uppsala, Sweden, SE Department of Psychology, University of California Berkeley, Berkeley, California 94720, USA, US
|
| |
Abstract: | The populations of gonadotropin-releasing hormone (GnRH)-producing cells within the preoptic area (POA) and terminal nerve
(TN) of the brain have been suggested as the neuronal systems mediating social control of sex and gonadogenesis in sequentially
hermaphroditic teleosts. In the present study, the number and soma size of GnRH-immunoreactive (GnRH-ir) cells in the POA
and TN were studied in male, female and juvenile individuals of the dusky anemonefish (Amphiprionmelanopus), a species which displays both male to female sex change and socially controlled sexual maturation. The results showed that
the number of POA (but not TN) GnRH-ir cells differ significantly between sexual phases, with males displaying higher cell
numbers than both females and juveniles. Soma sizes of POA and TN GnRH-ir cells were larger in females than in males and juveniles.
However, this relationship was fully explained by differences in body size. The results indicate that high POA GnRH cell numbers
are part of a masculinizing mechanism and support the hypothesis that the POA GnRH cell population plays a central role in
initiating or mediating the process of socially induced gonadal and/or behavioural transformations in sequential hermaphrodites.
Accepted: 9 June 1997 |
| |
Keywords: | Sex change Teleost Pomacentridae Amphiprion Gonadotropin-releasing hormone (GnRH) |
本文献已被 SpringerLink 等数据库收录! |
|