Linked Life Data

10495416

Source:http://linkedlifedata.com/resource/pubmed/id/10495416

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-5-1
pubmed:abstractText
Progestins are believed to exert positive effects on bone density through receptors located in osteoblasts. In the present studies, the binding characteristics and regulation of the progestin receptors in two osteoblast-like cell lines were compared with those in human breast lines. Human TE85 and murine MC3T3-E1 osteoblast-like cells contain a single, high-affinity progestin binding site whose affinity and concentration are lower than in human breast cells. The osteoblastic progestin binding sites showed the expected steroid specificity and associated with the cell nuclei when occupied by ligand. The progestin receptors in osteoblastic cells also had sedimentation coefficients similar to those receptors in breast cells. The regulation of the progestin receptor in the osteoblast-like cells was explored by treating them with estradiol. In contrast to the large, rapid change seen in the breast cells, the progestin receptor levels in the MC3T3-E1 cells showed only a small, delayed up-regulation with estradiol treatment. The progestin receptor number in the TE85 cells was unaffected by estradiol. Down-regulation of the progestin receptors was explored by treating the cells with the progestin, norethindrone (NET). NET administration produced a rapid drop in progestin binding sites in the breast cells and a smaller, more gradual decline in MC3T3-E1 progestin binding. While the maximal decrease in receptor number occurred within 24 h in the breast cells, the receptor number was still continuing to fall after 72 h in the MC3T3-E1 cells. The data presented here demonstrate that both human and murine osteoblast-like cells contain a functional progestin receptor whose binding characteristics and regulation are similar, but not identical, to those receptors in other progestin target tissues such as the breast.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-0795
pubmed:author
pubmed:issnType
Print
pubmed:volume
163
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
139-47
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Characterization of the progestin receptors in the human TE85 and murine MC3T3-E1 osteoblast-like cell lines.
pubmed:affiliation
The RW Johnson Pharmaceutical Research Institute, Route 202, Raritan, New Jersey 08869, USA.
pubmed:publicationType
Journal Article