Linked Life Data

2754359

Source:http://linkedlifedata.com/resource/pubmed/id/2754359

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-8-30
pubmed:abstractText
The effect of administration of bovine somatotrophin (bST) on peripheral conversion of thyroxine (T4) to tri-iodothyronine (T3) was studied in non-pregnant lactating Holstein cows. Six cows were injected daily for 5 days with 40 mg recombinantly derived bST, while six control cows received excipient alone. Blood samples were collected hourly from 08.00 to 19.00 h on a single day the week before treatment and on days 4-5 of treatment. All other tissue samples were obtained at slaughter, 20-23 h after the last injection. Administration of bST increased milk production and caused a 9% increase in hepatic DNA. Consumption of feed did not differ between control and bST-treated cows. Treatment did not alter serum concentrations of T4 or T3, although concentrations of thyroid hormones in the serum increased from 08.00 to 19.00 h. Activity of thyroxine-5'-monodeiodinase (5'-D) in liver and kidney was similarly unaffected. However, activity of 5'-D in mammary tissue increased approximately twofold in response to bST administration. We suggest that an increase in mammary conversion of T4 to the more biologically potent thyroid hormone T3 plays a role in mediating the galactopoietic response of dairy cattle to bST.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-0795
pubmed:author
pubmed:issnType
Print
pubmed:volume
121
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-11
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Somatotrophin increases thyroxine-5'-monodeiodinase activity in lactating mammary tissue of the cow.
pubmed:affiliation
Milk Secretion and Mastitis Laboratory, USDA, Beltsville, Maryland 20705.
pubmed:publicationType
Journal Article