Linked Life Data

8023919

Source:http://linkedlifedata.com/resource/pubmed/id/8023919

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 1
pubmed:dateCreated
1994-7-29
pubmed:abstractText
Although the production of thyroxine (T4) in the developing ovine fetus ranges from 20 to 50 micrograms.kg-1.day-1, production rates for 3,5,3'-triiodothyronine (T3) average only 1-2 micrograms.kg-1.day-1, whereas reverse T3 (rT3) production rates approach 5-6 micrograms.kg-1.day-1. Thus the fate of the majority of fetal T4 production is uncertain. Recently we have reported significant concentrations of various thyroid hormone sulfoconjugates in serum and other fetal compartments. In the present study, we used steady-state kinetic techniques in developing sheep to establish the clearance and production rates for T4, T3, and rT3 sulfates. These studies confirm that T4, T3, and rT3 sulfate are predominant metabolites of thyroid hormone in the developing ovine fetus. Plasma clearance rates for T3, T4, and rT3 sulfates are low in the fetus, averaging 0.67 +/- 0.07, 1.46 +/- 0.11, and 4.1 +/- 1 ml.kg-1.min-1, respectively. Clearance rates for these thyrosulfoconjugates increase two to fourfold postnatally, probably reflecting increased activity of 5'-monodeiodinase after birth. Moreover, fetal production rates for these sulfated thyroid hormone metabolites exceed those of 2-wk-old sheep 4- to 10-fold. The data suggest that a significant route of fetal T4 metabolism is sulfation followed by deiodination to rT3 sulfate.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E892-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Metabolism of sulfoconjugated thyroid hormone derivatives in developing sheep.
pubmed:affiliation
Perinatal Laboratories, Harbor-University of California Los Angeles Medical Center, Torrance 90509.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.