Linked Life Data

9015755

Source:http://linkedlifedata.com/resource/pubmed/id/9015755

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-5-12
pubmed:abstractText
In the present investigation, we have tested the hypothesis that calpain expression or activity in skeletal muscle is influenced by changes in mechanical loading in vivo. Muscle unloading for 10 days produced no change in the concentrations of calpain I, or II, and no change in calpain activation, as assessed by measurements of the proportion of calpain I or II isoforms that exhibited autoproteolytic modifications. However, muscle reloading for 2 days produced a 90% increase in calpain II concentration per unit wet weight of muscle relative to ambulatory controls. Although no change in the activation index for calpain I or II was identified for reloaded muscle, this index is an expression of the proportion of the total mass of each calpain isoform that is autoproteolyzed. Thus, there is also approximately a 90% increase in autolyzed calpain II in muscle experiencing increased loading than in controls. Northern analysis shows that the concentration of mRNA for calpain II is increased in reloaded muscle, but no change in calpain II mRNA concentration in unloaded muscle. In situ reverse transcription polymerase chain reaction was used to confirm that nearly all calpain II mRNA in reloaded muscle is located in muscle fibers, with very little detectable calpain II mRNA in non-muscle cells present in the tissue. Together, these findings show that increased muscle loading causes a selective increase in the expression of calpain II isoform, thereby indicating that its regulation is independent from other calpain isoforms.
pubmed:grant
pubmed:keyword
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0730-2312
pubmed:author
pubmed:issnType
Print
pubmed:volume
64
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
55-66
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Calpain II expression is increased by changes in mechanical loading of muscle in vivo.
pubmed:affiliation
Department of Physiological Science, University of California, Los Angeles 90095-1527, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't