Sex steroids and cortisol levels in the blood of stellate sturgeon (Acipenser stellatus Pallas) during final maturation induced by LH-RH-analogue

Blood serum cortisol (F), testosterone (T), 11-ketotestosterone (11KT), oestradiol-17 (E2), progesterone (P4), 17,20,21-trihydroxy- 4-pregnen-3-one (20βS) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) concentrations were measured by enzyme linked immuno-sorbent assay (ELISA) and radio-immunoassay (RIA) in stellate sturgeon (Acipenser stellatus, Pallas) during final maturation (FM) induced by luteinizing hormone-releasing hormone analogue (LH-RH-A). After the LH-RH-A treatment there was a significant elevation of sex steroids (T, E2, P4, 20βS) and F levels before ovulation and decrease of T and E2 levels after ovulation. In males at the beginning of spermiation LH-RH-A induced a rise of sex steroids and F levels. There was a decrease of steroids levels at the end of spermiation. The data indicates a possible role of 20βS takes part in FM in stellate sturgeon male as well as in female. The rise in F levels may indicate an interaction between corticosteroids and gamete maturation in stellate sturgeon