Linked Life Data

8308462

Source:http://linkedlifedata.com/resource/pubmed/id/8308462

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-3-11
pubmed:abstractText
We have previously found that administration of oestradiol-17 beta (OE2) to intact adult female rats of 19 days stimulates cancellous bone formation. However, this effect is not observed following longer periods of OE2 treatment, suggesting that the responsiveness of the skeleton to oestrogen's anabolic action is reduced after prolonged administration. A possible explanation for this is that oestrogen also suppresses bone resorption, which is an important stimulus for bone formation. We therefore investigated the effect of omitting OE2 for short periods, on the proximal tibial metaphysis of intact female rats. We found that, unlike continuous treatment with OE2 (40 micrograms/kg) for 56 days, omission of OE2 for 4 days out of every 20 was associated with a significant increase in cancellous bone volume. Although continuous and intermittent OE2 were both associated with a reduction in osteoclast surface, a decrease in the proportion of double fluorochrome-labelled surface was only seen after continuous OE2 treatment. We then studied the effects of longer periods of OE2 omission by giving OE2 (40 micrograms/kg) for three repeated cycles of: (1) OE2 for 16 days/vehicle for 4 days, (2) OE2 for 12 days/vehicle for 8 days, (3) OE2 for 8 days/vehicle for 12 days, or (4) OE2 for 4 days/vehicle for 16 days. We found a significant increase in cancellous bone volume when OE2 was stopped for either 4 or 8 days at a time. However, longer periods of OE2 omission did not affect bone volume, possibly because these were associated with an increase in bone resorption and/or a reduction in bone formation during the OE2-free period.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-0795
pubmed:author
pubmed:issnType
Print
pubmed:volume
139
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
267-73
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Prolonged intermittent but not continuous administration of oestradiol-17 beta increases bone volume in the rat.
pubmed:affiliation
Department of Histopathology, St George's Hospital Medical School, London.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't