Hormonal regulation of hepatic IGF‐I and IGF‐II gene expression in the Marine Teleost Sparus aurata

Hormonal regulation of hepatic IGF‐I and IGF‐II gene expression in the Marine Teleost Sparus... The present work aimed to determine whether GnRH potentiates the effect of growth hormone (GH) on insulin‐like growth factors (IGF‐I and IGF‐II) hepatic gene expression in Sparus aurata liver. Since several hepatic genes were shown to underlie direct regulation via the hepatic estrogen receptor, another aim was to extend our understanding of direct estrogen effects on liver IGFs gene expression. Pre‐reproductive sea bream females were treated with GH, GnRH, estradiol‐17β, GH plus GnRH, and estradiol‐17β plus GH. After 72 hr, all treatment induced an increase of plasma estradiol well correlated with the increase of plasma vitellogenin (VTG) levels. IGF‐I and IGF‐II expression in the liver of treated females was determined by semi‐quantitative RT‐PCR, using beta‐actin as internal standard. The results reported here show that GH significantly stimulates hepatic transcription of IGF‐I and IGF‐II genes. Surprisingly, E2 and GnRH treatments decreased both IGF‐I and IGF‐II mRNA levels. In fishes treated with GH plus GnRH, the GnRH contrasted the GH effect: the IGF‐I mRNA levels were still significantly higher than in controls, while the effect of GH on IGF‐II gene expression was totally abolished. At the same time, in the combined treatment with GH plus E2, the E2 counteracted the stimulatory effect of GH on both IGF‐I and IGF‐II genes expression. Mol. Reprod. Dev. 71: 12–18, 2005. © 2005 Wiley‐Liss, Inc. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Molecular Reproduction & Development Wiley

Hormonal regulation of hepatic IGF‐I and IGF‐II gene expression in the Marine Teleost Sparus aurata

Loading next page...
 
/lp/wiley/hormonal-regulation-of-hepatic-igf-i-and-igf-ii-gene-expression-in-the-n0oJb0jpHs
Publisher
Wiley
Copyright
Copyright © 2005 Wiley‐Liss, Inc., A Wiley Company
ISSN
1040-452X
eISSN
1098-2795
D.O.I.
10.1002/mrd.20122
Publisher site
See Article on Publisher Site

Abstract

The present work aimed to determine whether GnRH potentiates the effect of growth hormone (GH) on insulin‐like growth factors (IGF‐I and IGF‐II) hepatic gene expression in Sparus aurata liver. Since several hepatic genes were shown to underlie direct regulation via the hepatic estrogen receptor, another aim was to extend our understanding of direct estrogen effects on liver IGFs gene expression. Pre‐reproductive sea bream females were treated with GH, GnRH, estradiol‐17β, GH plus GnRH, and estradiol‐17β plus GH. After 72 hr, all treatment induced an increase of plasma estradiol well correlated with the increase of plasma vitellogenin (VTG) levels. IGF‐I and IGF‐II expression in the liver of treated females was determined by semi‐quantitative RT‐PCR, using beta‐actin as internal standard. The results reported here show that GH significantly stimulates hepatic transcription of IGF‐I and IGF‐II genes. Surprisingly, E2 and GnRH treatments decreased both IGF‐I and IGF‐II mRNA levels. In fishes treated with GH plus GnRH, the GnRH contrasted the GH effect: the IGF‐I mRNA levels were still significantly higher than in controls, while the effect of GH on IGF‐II gene expression was totally abolished. At the same time, in the combined treatment with GH plus E2, the E2 counteracted the stimulatory effect of GH on both IGF‐I and IGF‐II genes expression. Mol. Reprod. Dev. 71: 12–18, 2005. © 2005 Wiley‐Liss, Inc.

Journal

Molecular Reproduction & DevelopmentWiley

Published: May 1, 2005

Keywords: estradiol; GnRH; GH; sea bream; multihormonal control; vitellogenin

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off