Linked Life Data

11760843

Source:http://linkedlifedata.com/resource/pubmed/id/11760843

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2001-12-11
pubmed:abstractText
The Lewis dwarf (DW) rat was used as a model to test the hypothesis that growth hormone (GH) is permissive for new bone formation induced by mechanical loading in vivo. Adult female Lewis DW rats aged 6.2 +/- 0.1 months (187 +/- 18 g) were allocated to four vehicle groups (DW), four GH treatment groups at 32.5 microg/100 g body mass (DWGH1), and four GH treatment groups at 65 microg/100 g (DWGH2). Saline vehicle or GH was injected intraperitoneally (ip) at 6:30 p.m. and 6:30 a.m. before mechanical loading of tibias at 7:30 a.m. A single period of 300 cycles of four-point bending was applied to right tibias at 2.0 Hz, and magnitudes of 24, 29, 38, or 48N were applied. Separate strain gauge analyses in 5 DW rats validated the selection of loading magnitudes. After loading, double-label histomorphometry was used to assess bone formation at the periosteal surface (Ps.S) and endocortical surface (Ec.S) of tibias. Comparing left (unloaded) tibias among groups, GH treatment had no effect on bone formation. Bone formation in tibias in DW rats was insensitive to mechanical loading. At the Ec.S, mechanically induced lamellar bone formation increased in the DWGH2 group loaded at 48N (p < 0.05), and no significant increases in bone formation were observed among other groups. The percentage of tibias expressing woven bone formation (Wo.B) at the Ps.S was significantly greater in the DWGH groups compared with controls (p < 0.05). We concluded that GH influences loading-related bone formation in a permissive manner and modulates the responsiveness of bone tissue to mechanical stimuli by changing thresholds for bone formation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0884-0431
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2284-90
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Growth hormone is permissive for skeletal adaptation to mechanical loading.
pubmed:affiliation
Department of Anatomical Sciences, The University of Queensland, Brisbane, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't