Linked Life Data

15113939

Source:http://linkedlifedata.com/resource/pubmed/id/15113939

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-4-28
pubmed:abstractText
After parturition, increased growth hormone (GH) secretion is important to preserve the metabolic homeostasis of energy-deficient dairy cows. Elevated plasma GH promotes lipid mobilization from adipose tissue, but paradoxically, is associated with depressed concentration of insulin-like growth factor-I (IGF-I), a growth factor produced in a GH-dependent fashion in liver. Primary factors regulating GH responses of liver and adipose tissue are poorly understood in periparturient dairy cows. Consistent with insulin being such a factor, its plasma concentration declined concomitantly with net energy balance (EB) and with plasma IGF-I in a group of 9 periparturient dairy cows. To test the role of insulin in regulating cellular determinants of GH responsiveness, hyperinsulinemic-euglycemic clamps were performed on 6 dairy cows in late pregnancy (28 d prepartum) before the reductions in EB, insulin, and IGF-I were initiated, and when they were completed in early lactation (10 d postpartum). Infusion of insulin nearly doubled the plasma concentration of IGF-I (P < 0.001) and hepatic levels of IGF-I mRNA during both states (P < 0.05). In liver, these responses were associated with increased abundance of the GH receptor protein (GHR; P < 0.05), whereas the abundance of intracellular mediators of GH actions (JAK2, STAT5, or STAT3) remained unaffected. Insulin also doubled GHR abundance in adipose tissue (P < 0.01), indicating that this effect is not liver specific. These results raise the possibility that insulin regulates the efficiency of GH signaling in liver and adipose tissue of dairy cows by acting as a rheostat of GHR synthesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-3166
pubmed:author
pubmed:issnType
Print
pubmed:volume
134
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1020-7
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Insulin increases the abundance of the growth hormone receptor in liver and adipose tissue of periparturient dairy cows.
pubmed:affiliation
Department of Animal Science, Cornell University, Ithaca, NY 14853-4801, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't