Logo image
Analysis of excitation‐contraction‐coupling components in chronically stimulated canine skeletal muscle
Journal article   Open access

Analysis of excitation‐contraction‐coupling components in chronically stimulated canine skeletal muscle

Kay OHLENDIECK, F. Norman BRIGGS, K. Francis LEE, Andrew W WECHSLER and Kevin P CAMPBELL
European journal of biochemistry, Vol.202(3), pp.739-747
12/1991
DOI: 10.1111/j.1432-1033.1991.tb16428.x
PMID: 1662614
url
https://doi.org/10.1111/j.1432-1033.1991.tb16428.xView
Published (Version of record) Open Access

Abstract

The chronic stimulation of predominantly fast‐twitch mammalian skeletal muscle causes a transformation to physiological characteristics of slow‐twitch skeletal muscle. Here, we report the effects of chronic stimulation on the protein components of the sarcoplasmic reticulum and transverse tubular membranes which are directly involved in excitation‐contraction coupling. Comparison of protein composition of microsomal fractions from control and chronically stimulated muscle was performed by immunoblot analysis and also by staining with Coomassie blue or the cationic carbocyanine dye Stains‐all. Consistent with previous experiments, a greatly reduced density was observed for the fast‐twitch isozyme of Ca2+‐ATPase, while the expression of the slow‐twitch Ca2+‐ATPase was found to be greatly enhanced. Components of the sarcolemma (Na+/K+‐ATPase, dystrophin‐glycoprotein complex) and the free sarcoplasmic reticulum (Ca2+‐binding protein sarcalumenin and a 53‐k Da glycoprotein) were not affected by chronic stimulation. The relative abundance of calsequestrin was slightly reduced in transformed skeletal muscle. However, the expression of the ryanodine receptor/Ca2+‐release channel from junctional sarcoplasmic reticulum and the transverse tubular dihydropyridine‐sensitive Ca2+ channel, as well as two junctional sarcoplasmic reticulum protiens of 90 kDa and 94 kDa, was greatly suppressed in transformed muscle. Thus, the expression of the major protein components of the triad junction involved in excitation‐contraction coupling is suppressed, while the expression of other muscle membrane proteins is not affected in chronically stimulated muscle.

Details

Metrics

Logo image