Linked Life Data

17786946

Source:http://linkedlifedata.com/resource/pubmed/id/17786946

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2007-12-26
pubmed:abstractText
Bone elongation is predominantly driven by the volume expansion of growth plate chondrocytes. This mechanism was initially believed to be "hypertrophy", describing a proportional increase of cell water and organelles. However, morphometrical analysis subsequently assumed the increase to be "swelling", resulting in a disproportionate increase of cell water (osmotically active fraction). Histological approaches were performed on fixed tissue, and for the "swelling" assumption to be valid, the osmotic sensitivity of living cells before and during volume increase should differ. To test this, analysis of images acquired by 2-photon laser scanning microscopy (2PLSM) were used to determine the osmotic sensitivity, and osmotically active/inactive proportions of in situ chondrocytes from 15 living rat growth plates exposed to varying media osmolarities ( approximately 0-580 mOsm). The dimensions of cell volume swelling in hypotonic media were different to the preferential lengthening seen in vivo, confirming the complexity of directional cell volume increase. Boyle-van't Hoff analysis of cell volume over the range of media osmolarity indicated no significant difference (Student's t-test) in the osmotically inactive fraction, 39.5 +/- 2.9% and 47.0 +/- 4.3% (n = 13) for proliferative and hypertrophic zones, respectively, or the sensitivity of volume to changes in media osmolarity (proliferative 15.5 +/- 0.8 and hypertrophic zone 15.5 +/- 1.2%volume . Osm). The osmotic fractions did not change as chondrocytes progress from proliferative to hypertrophic regions of the growth plate. Our data suggest cell volume increase by hypertrophy may play a greater role in cell enlargement than swelling, and should be re-evaluated as a mechanism responsible for growth plate chondrocyte volume increase and hence bone elongation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1097-4652
pubmed:author
pubmed:copyrightInfo
(c) 2007 Wiley-Liss, Inc.
pubmed:issnType
Electronic
pubmed:volume
214
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
621-9
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
The osmotic sensitivity of rat growth plate chondrocytes in situ; clarifying the mechanisms of hypertrophy.
pubmed:affiliation
Centre for Integrative Physiology, School of Biomedical Sciences, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh, Scotland, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't