Steroidogenesis in the gonads of rainbow trout fry (Salmo gairdneri) before and after the onset of gonadal sex differentiation

Hurk, R. van den; Lambert, J.G.D.; Peute, J.

doi:10.1051/rnd:19820313

Cited by 94 publications

(19 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The basal levels of rtER mRNA are very similar to those found in the adult, and on Northern blot (result not shown) the presence of the two rtER mRNAs was noted. rtER and Vg genes also seem to be fully induced as early as at hatching and our results show that the estrogen response arises independently of sexual maturation which occurs later during development (Van den Hurk et al, 1982). These results are in good agreement with previous studies on chicken yolk Male rainbow trout (600-900 g) were injected with E, (1.5 mg/kg) or with the solvent.…”

Section: Discussionsupporting

confidence: 92%

In vivo estrogen induction of hepatic estrogen receptor mRNA and correlation with vitellogenin mRNA in rainbow trout

Pakdel

Féon

Gac

et al. 1991

Molecular and Cellular Endocrinology

160

View full text Add to dashboard Cite

SummaryWe have previously described the cloning, sequencing and in vitro expression of a full-length rainbow trout estrogen receptor cDNA (rtER cDNA). This full cDNA randomly labelled was used to study the estrogen induction of hepatic rtER mRNA in correlation with vitellogenin (Vg) mRNA in different physiolo~cal situations.In this paper, we show that in the liver two mRNA species are under hormonal control and their level increases about g-fold after estrogen stimulation.These two mRNAs are expressed and induced in the liver as early as the hatching stage in correlation with the expression of Vg mRNA. A long-term analysis of rtER mRNA after estradiol (E2) injection shows a transient induction of the nuclear ER and its mRNA which recover to the basal level after 2 weeks. Nevertheless, a memory effect was observed on the expression of the Vg gene which does not appear to be directly related to the estrogen receptor level.

show abstract

Section: Discussionsupporting

confidence: 92%

In vivo estrogen induction of hepatic estrogen receptor mRNA and correlation with vitellogenin mRNA in rainbow trout

Pakdel

Féon

Gac

et al. 1991

Molecular and Cellular Endocrinology

160

View full text Add to dashboard Cite

show abstract

“…Nevertheless, in many species, testosterone seems to play an important role in sex differentiation and is closely related to gonadal differentiation [6,8,13,14,20]. In the present study, the testosterone peak observed at D30-D35 could be associated with the occurrence of sex differentiation in Eurasian perch [30], but as for other fish species, it was not possible to conclude if it is a cause or a consequence of gonadal differentiation [8,15,19,20]. The high levels of 11KT (median: 431.5 pg g À1 ) in mixed-sex groups and the lack of a detectable level in all-female batches suggest that this steroid was particularly important for male sex differentiation in Eurasian perch.…”

Section: Discussioncontrasting

confidence: 44%

“…These ''maternal'' sex steroids could be used as precursors to induce the initial sexual differentiation of the brain and/or the gonads. Sex steroid hormones are principally synthesized in gonad, although non-gonadal tissues, such as brain, blood, kidney or liver, can also synthesize these hormones [10,14,19,35]. The detection or presence of significant levels of testosterone, estradiol and 11keto-testosterone in embryos and developing larvae of Eurasian perch before the histological differentiation of the gonad strongly suggest an extra-gonadal synthesis of these sex steroid hormones in Eurasian perch, as has been observed in Coho salmon [8] and tilapia [12].…”

Section: Discussionmentioning

confidence: 99%

“…In tilapia (Oreochromis niloticus), rainbow trout (Oncorhynchus mykiss) and grey mullet (Mugil cephalus) ultrastructural studies of the gonad during the process of sex differentiation have demonstrated the presence of androgens, particularly 11KT and 11-oxygenated androgens, before the onset of sexual differentiation and pointed up their role in sex determination [18][19][20]. Studies of sex steroid hormones levels and gene expression of 11b-hydroxylase (enzyme involved in the biosynthesis of the 11b-hydroxytestosterone and 11b-hydroxyandrostenedione) during sex differentiation in tilapia and rainbow trout also demonstrated the importance of these steroids in this process [13,21,22].…”

Section: A U T H O R ' S P E R S O N a L C O P Ymentioning

confidence: 99%

See 1 more Smart Citation

Sex steroid dynamics during embryogenesis and sexual differentiation in Eurasian perch, Perca fluviatilis

et al. 2007

View full text Add to dashboard Cite

It is widely accepted that sex steroid hormones play an important and a specific role during the process of sex differentiation in fish. In order to describe the role of the three main sex steroid hormones (testosterone-T, 17b-estradiol-E2 and 11keto-testosterone-11KT) during embryogenesis and sex differentiation in Eurasian perch, Perca fluviatilis, eggs, larvae and juveniles originating from two mixed-sex and two all-female progenies were regularly sampled from fertilization to hatching (D0) and from hatching to day 70 post-hatching (D70). Just after spawning, a significant amount of sex steroids [T (1634.2 pg g ) and significantly increased after the onset of the histological differentiation of the gonad in both progenies (D35). Levels of 11KT were significantly higher in mixed-sex (median: 431.5 pg g À1) than in all-female progenies (below the limit of assay detection) and significantly increased at D35 in all-female progenies (median value: 343.2 pg g À1 ). Mean 11KT to E2 ratio was six-fold higher in mixed-sex progenies (1.35) than in all-female progenies (0.24). The data suggest that the 11-oxygenated androgen (11KT) plays a major role in the male differentiation process, and that sex differentiation in Eurasian perch is probably determined by the 11KT to E2 ratio. #

show abstract

“…These results together with ultrastructural (Oota and Yamamoto 1966;Van den Hurk et al 1982) and enzymocytochemical features (Van den Hurk et al 1982) indicate that interstitital steroidogenic cells are already functional in immature testes, and could be responsible for 17a20IOHP synthesis.…”

Section: Discussionmentioning

confidence: 58%

Synthesis and regulation of 17α-hydroxy-20β-dihydroprogesterone in immature males of Oncorhynchus mykiss

Vizziano

Gac

Fostier

1995

Fish Physiol Biochem

View full text Add to dashboard Cite

Three experimental approaches were chosen to study the question if the progestin 17α-hydroxy-20β-dihydroprogesterone (17α20βOHP) is synthesised in testes of young Oncorhynchus mykiss, in which the absence of spermatozoa was verified histologically: first, in order to detect 20β-hydroxysteroid dehydrogenase activity (20βHSD), testes homogenates were incubated with (3)H-labeled 17αOHP.Metabolites were analysed by TLC, HPLC, and repeated crystallization to constant isotope ratios. One of the metabolites was identified as 17α20βOHP-(3)H, indicating that already immature testes contain 20βHSD activity and are able to produce 20β-reduced steroids. Second, 17α20βOHP was quantified by radioimmunoassay in incubates of testes fragments. The sensitivity of the gonads to gonadotropin II (GtH II) became evident when comparing incubations in the absence and presence of GtH II. Third, plasma levels of 17α20βOHP were significantly higher in animals injected with partially purified salmon gonadotropin, compared to controls. Thus, for the first time, it could be shown that 20βHSD is present in testicular cells other than spermatozoa. Furthermore, 17α20βOHP is indeed secreted at a very early stage of testicular development; 17α20βOHP secretion is also responsive to GtH II. Future studies will have to show if the functions of this progestin include the stimulation of spermatogenesis.

show abstract

Steroidogenesis in the gonads of rainbow trout fry (Salmo gairdneri) before and after the onset of gonadal sex differentiation

Abstract: Summary. Gonadal Introduction.

Cited by 94 publications

References 15 publications

In vivo estrogen induction of hepatic estrogen receptor mRNA and correlation with vitellogenin mRNA in rainbow trout

In vivo estrogen induction of hepatic estrogen receptor mRNA and correlation with vitellogenin mRNA in rainbow trout

Sex steroid dynamics during embryogenesis and sexual differentiation in Eurasian perch, Perca fluviatilis

Synthesis and regulation of 17α-hydroxy-20β-dihydroprogesterone in immature males of Oncorhynchus mykiss

Contact Info

Product

Resources

About