To examine the roles of gonadal steroids in the regulation of expression of gonadotropin subunit genes, male red seabream were gonadectomized and a sub-group was treated with 11-ketotestosterone (11-KT). Castration of males during the early stage of spermatogenesis elicited a significant increase in FSHβ mRNA levels, which was prevented by 11-KT replacement. By contrast, LHβ mRNA levels were not changed by castration or 11-KT replacement. In addition, administration of 11-KT to sham-operated males suppressed the steady-state FSHβ and LHβ mRNA levels. These results indicate that 11-KT may function as a negative feedback regulator of FSHβ gene expression, and may act through the testis to down-regulate LHβ mRNA levels in male red seabream during this period.
|Number of pages||2|
|Journal||Fish Physiology and Biochemistry|
|Publication status||Published - 2003|
All Science Journal Classification (ASJC) codes
- Aquatic Science