Data/hora: 10/06/2024 04:54:40

Provedor de dados: | 5
País: | France
Título: | Role of steroid hormones and external factors in the control of pituitary gonadotropic activity of female European eel (Anguilla anguilla ).
Autores: | Leloup, H; Fontaine, Y; Dufour, S; Querat, B.
Data: | 1983-12
Ano: | 1983
Palavras-chave: | Anguilla anguilla; Anguillidae; Pisces; Migrations; Salinity; Environmental factors; Pituitary gland; Sexual reproduction; Ovaries; Sexual maturity; Steroids; Sex hormones; Facteurs externes; Steroids sexuels; Gonadotropine; Anguille.
Resumo: | Gonadotropic activity is relatively low in the female freshwater (FW) eel (A. anguilla ): pituitary GTH was about 15 ng equivalent cGTH/mg fresh tissue. Plasma GTH was always less than 1 ng equivalent cGTH/ml and often undetectable (&lt; 0.2 ng equivalent cGTH/ml). Ovarian steroidogenesis in FW fish is similarly low; plasma concentration of both free testosterone (T) and free estradiol (E sub(2)) were less than 0.3 ng/ml as measured by RIA. Treatment with E sub(2) in FW fish caused a great increase in pituitary GTH, up to 1000 times control values, without changing plasma GTH. Stimulation of gonadotropic activity and ovarian development occur during the eel's migration to the Sargasso Sea. Adaptation to seawater (SW) caused a great increase of plasma E sub(2) concentration without modifying that of T. However, adaptation to SW did not cause any detectable change in gonadotropic activity or ovarian development.
Tipo: | Text
Idioma: | Inglês
Identificador: | http://archimer.ifremer.fr/doc/1983/acte-1217.pdf
Editor: | Actes de colloques. Ifremer. Brest [ACTES COLLOQ. IFREMER.]. 1985
Relação: | http://archimer.ifremer.fr/doc/00000/1217/
Formato: | application/pdf