ISSN:
1573-5168
Keywords:
11KT
;
steroidogenesis
;
plasma steroids
;
ovary
;
sturgeon
;
Acipenser baeri
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract High levels of 11-ketotestosterone (11KT) were found (49 to 160 ng ml−1) in plasma of Siberian sturgeon females during the end of their reproductive cycle. These levels were measured either by specific radioimmunoassay, or both by specific radioimmunoassay and by UV absorption after HPLC (isocratic conditions, 33% methanol, 26% acetonitrile, 41% water). In order to find the origin of 11KT synthesis, ovaries were incubated (30 min and 2h at 20°C) with tritiated 17-hydroxyprogesterone (17OHP) or with tritiated androstenedione (A4). Testosterone (conversion rate from tritiated 17OHP: 4%) and 11-ketotestosterone (conversion rate from tritiated A4: 1.6%) were identified as metabolites of respectively 17OHP and A4 (TLC, HPLC and crystallization). 11β-hydroxyandrostenedione (11βOHA4) and 11β-hydroxytestosterone (11βOHT) were suggested to be intermediate metabolites. Besides interrenal and blood cells were incubated respectively with tritiated cortisol and tritiated A4. 11βOHA4 was identified in interrenal incubation (yield from tritiated cortisol: 1.2%). 11KT in interrenal (yield from tritiated cortisol: 0.14%), and 11βOHA4 and 11KT in blood cells (yield from tritiated A4: 1.6%), were suspected to be synthesized (TLC, HPLC, acetylation). No significant metabolization of tritiated cortisol could be found in liver. The possible contribution of each of these tissues to high 11KT levels found in plasma is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00004069
Permalink
