Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-4-5
pubmed:abstractText
Although sex hormones are important in the attainment and maintenance of bone mass, the mechanism by which they exert their effect is unknown. We therefore tested the effects of estradiol-17 beta, dihydrotestosterone, and progesterone on osteoclasts, the cells that resorb bone. Osteoclasts were disaggregated from neonatal rat long bones, and incubated with or without the addition of osteoblastic cells or osteoblast-like cell lines. Bone resorption was assessed by scanning electron microscopy as the extent of excavation of the bone surface after incubation. We found dihydrotestosterone (1-100 nmol/l) and progesterone (10-1000 nmol/l) to have no significant effect on bone resorption. By contrast, E2 (1 nmol/l) reduced bone resorption in osteoclast cultures to which osteoblasts had been added, by approximately 25%, although consistent inhibition with other concentrations (0.01, 0.1, 10 nmol/l) was not observed. To our surprise, E2 was also associated with a delayed, dose-responsive, stimulation of bone resorption, in the range 0.1-10 nmol/l, in osteoclast cultures free from added osteoblastic cells. Tamoxifen, which itself had no effect on bone resorption, appeared to antagonise these E2 effects. Although the physiological significance of the stimulatory effect is unclear, we hypothesize that its presence prevented us, and previous workers, from observing dose-responsive inhibition of bone resorption by E2 in vitro.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0001-5598
pubmed:author
pubmed:issnType
Print
pubmed:volume
124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
121-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
The effect of sex hormones on bone resorption by rat osteoclasts.
pubmed:affiliation
Department of Pathology, St. George's Hospital Medical School, London, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't