Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1986-11-18
pubmed:abstractText
Thyroxine (T4) and triiodothyronine (T3) activate Na+-dependent inorganic phosphate (Pi) transport in organ-cultured embryonic chick small intestine. Induction of transport activity requires intact protein synthesis and can be expressed in enterocytes with varying degrees of differentiation. T3 and T4 exert their effect independent of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), which is shown to stimulate Pi uptake only in the final stage of embryonic differentiation. At this time point, a potentiating effect of 1,25(OH)2D3 and T4 on Pi transport in cultured jejunum can be demonstrated. Thyroid hormones appear to stimulate Na+ gradient-driven Pi transport without concomitantly raising (Na+-K+)-ATPase activity. T4 has no influence whatsoever on calcium uptake by cultured embryonic small intestine while 1,25(OH)2D3 is effective at all stages of embryonic development investigated (day 15-20). However, when both hormones were present in the culture medium, the effect of 1,25(OH)2D3 on calcium transport is doubled. Our results suggest that the hyperphosphataemia associated with hyperthyroidism is likely to result, at least in part, from the independent effect of thyroid hormones as well as from their potentiation of the 1,25(OH)2D3 action on Na+-dependent intestinal Pi transport. In addition, their permissive effect on 1,25(OH)2D3-induced calcium absorption provides an explanation for unaltered calcium absorption in a number of hyperthyroid patients, although reduced plasma levels of 1,25(OH)2D3 are generally observed in this condition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0001-5598
pubmed:author
pubmed:issnType
Print
pubmed:volume
113
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
96-103
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Intestinal phosphate and calcium absorption: joint regulation by thyroid hormones and 1,25-dihydroxyvitamin D3.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't