Linked Life Data

7674307

Source:http://linkedlifedata.com/resource/pubmed/id/7674307

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-10-19
pubmed:abstractText
Endothermic heat production and the capacity to shiver develop soon after hatching in birds, permitting chicks to regulate their body temperature. Physiological studies have not clearly identified the developmental events causing this change in function. Here, we use electron microscopy to examine the development of structures involved in muscle activation, contraction, and metabolism coincident with the development of shivering thermogenesis. A stereological study was used to compare the ultrastructure of chicken iliofibularis before endothermic heat production was present (24 h before hatching) and 120 h later, when the iliofibularis had substantial capacity for shivering. Profound increases were found in the t-tubule system and terminal cisternae, mitochondrial cristae, and lipids. The number of triadic profiles increased 3.8-fold (7.6 +/- 1.31/100 microns 2 to 28.5 +/- 2.90/100 microns 2 fiber area). The surface area of cristae per mitochondrial volume doubled (12.0 +/- 1.50 microns 2/microns 3 to 25.7 +/- 1.84 microns 2/microns 3). Lipid droplets were rare in the iliofibularis of embryos about to hatch, but accounted for 4.4% of the muscle fiber volume in day 4 birds. We suggest that these ultrastructural changes more fully activate the iliofibularis, allow it to produce more heat both from calcium pumping and from contraction, and increase its endurance, thus permitting the muscle to be effective in thermogenesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0362-2525
pubmed:author
pubmed:issnType
Print
pubmed:volume
225
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
357-67
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Perinatal changes in avian muscle: implications from ultrastructure for the development of endothermy.
pubmed:affiliation
Department of Physiology and Biophysics, University of Illinois, Chicago 60612-7342, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.