Seasonal changes in expression of LH-beta and FSH-beta in male and female three-spined stickleback, Gasterosteus aculeatus.
Gen Comp Endocrinol
; 145(3): 263-9, 2006 Feb.
Article
em En
| MEDLINE
| ID: mdl-16289183
ABSTRACT
In teleost fishes, like in other vertebrates, the gonadal development is stimulated by two gonadotropic hormones; luteinizing hormone (LH) and follicle-stimulating hormone (FSH). To achieve a better understanding of the role of gonadotropins in teleost reproduction; expression of LH-beta and FSH-beta mRNA and the status of gonads and secondary sexual characters were analyzed over the annual cycle in male and female three-spined sticklebacks, a species in which the development of male secondary sexual characters and spermatogenesis are separated in time. The kidney in the male stickleback hypertrophies during the breeding season and produces a glue used when building nests. Kidney weights, as well as levels of 11-ketotestosterone (11KT), reached a peak in May. Both testosterone (T) levels and the gonadosomatic index (GSI, gonad weight/body weight x 100) in females started to increase in April, and peaked in May as well. Later in summer, after the breeding season, these features declined. In females, LH-beta expression followed the GSI and T levels closely, levels were low during winter and early spring, increased to a peak in late May and declined to low levels again in July. FSH-beta expression peaked earlier, in January and declined slowly over spring. In males, LH-beta expression peaked in May. During June-September, when spermatogenesis was active, LH-beta levels were very low. FSH-beta expression peaked in January, earlier than LH-beta expression did, and reached the lowest levels in July. Thus, when spermatogenesis started at the end of summer, the expression of both GTH-beta mRNAs, and circulating 11KT, displayed their lowest levels.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Estações do Ano
/
Smegmamorpha
/
Subunidade beta do Hormônio Folículoestimulante
/
Hormônio Luteinizante Subunidade beta
Limite:
Animals
Idioma:
En
Revista:
Gen Comp Endocrinol
Ano de publicação:
2006
Tipo de documento:
Article