Linked Life Data

8575651

Source:http://linkedlifedata.com/resource/pubmed/id/8575651

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1996-3-14
pubmed:abstractText
Steroidogenesis in the gonad of the protandrous sea bass, Lates calcarifer, was examined in vitro in spermiating testis, previtellogenic ovary, and transitional gonads. Gonadal tissues were incubated with tritiated androstenedione. Metabolites were analyzed by thin-layer chromatography, high-performance liquid chromatography, microchemical reactions, and crystallization to constant specific activity. 17 beta-Hydroxysteroid dehydrogenase, 5 beta-reductase, and 3 alpha-hydroxysteroid dehydrogenase activities were found in all of the sex types. On the other hand, 11 beta-hydroxysteroid dehydrogenase and 11 beta-hydroxylase activities were found only when testicular tissue was present, i.e., in testis and early transitional gonad. A low aromatase activity leading to estrone synthesis was detected in the previtellogenic ovary. In late transitional gonads, a major metabolite (metabolite X) was suggestively identified as a 3-ester of 17 beta-estradiol according to its chemical and immunological characteristics. Levels of 17 beta-estradiol (E2), the metabolite X, testosterone (T), and 11-ketotestosterone (11KT) were also measured by radioimmunoassay in plasma, before (January and February) and during (March and April) the sex inversion process. Plasma E2 was virtually undetectable (means below 25 pg/ml), although higher levels of metabolite X were found in transitional fish (485 +/- 432 pg/ml in March). Throughout this period, plasma levels of T and 11KT and the androgens/estrogens ratio were significantly higher in males than in transitional fish, where these levels decreased during the sex inversion period. The level of in vitro synthesis of metabolite X was high in transitional gonads, but their concentrations were very low (0.07 +/- 0.09 ng of equivalent E2/g in transitional gonads against 0.22 +/- 0.37 ng of equivalent E2/g in testes and 2.16 +/- 2.7 ng of equivalent E2/g in ovaries).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0016-6480
pubmed:author
pubmed:issnType
Print
pubmed:volume
100
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
106-18
pubmed:dateRevised
2010-12-1
pubmed:meshHeading
pubmed-meshheading:8575651-11-beta-Hydroxysteroid Dehydrogenases, pubmed-meshheading:8575651-17-Hydroxysteroid Dehydrogenases, pubmed-meshheading:8575651-3-Hydroxysteroid Dehydrogenases, pubmed-meshheading:8575651-Androstenedione, pubmed-meshheading:8575651-Animals, pubmed-meshheading:8575651-Bass, pubmed-meshheading:8575651-Chromatography, High Pressure Liquid, pubmed-meshheading:8575651-Estradiol, pubmed-meshheading:8575651-Female, pubmed-meshheading:8575651-Hermaphroditic Organisms, pubmed-meshheading:8575651-Hydroxysteroid Dehydrogenases, pubmed-meshheading:8575651-Male, pubmed-meshheading:8575651-Ovary, pubmed-meshheading:8575651-Radioimmunoassay, pubmed-meshheading:8575651-Seasons, pubmed-meshheading:8575651-Sex Determination Processes, pubmed-meshheading:8575651-Testis, pubmed-meshheading:8575651-Testosterone
pubmed:year
1995
pubmed:articleTitle
Gonadal in vitro androstenedione metabolism and changes in some plasma and gonadal steroid hormones during sex inversion of the protandrous sea bass, Lates calcarifer.
pubmed:affiliation
Laboratoire de Physiologie des Poissons, INRA, Rennes, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't