MHC-based fiber type and E-C coupling characteristics in mechanically skinned muscle fibers of the rat
Goodman, Craig and Patterson, Michael and Stephenson, Gabriela (2003) MHC-based fiber type and E-C coupling characteristics in mechanically skinned muscle fibers of the rat. American journal of physiology: cell physiology, 284. c1448-c1459. ISSN 03636143Full text for this resource is not available from the Research Repository.
MHC-based fiber type and E-C coupling characteristics in mechanically skinned muscle fibers of the rat. Am J Physiol Cell Physiol 284: C1448–C1459, 2003. First published January 29, 2003; 10.1152/ajpcell.00569.2002.—In this study, we investigated whether the previously established differences between fast- and slow-twitch single skeletal muscle fibers of the rat, in terms of myosin heavy chain (MHC) isoform composition and contractile function, are also detectable in excitation-contraction (E-C) coupling. We compared the contractile responsiveness of electrophoretically typed, mechanically skinned single fibers from the soleus (Sol), the extensor digitorum longus (EDL), and the white region of the sternomastoid (SM) muscle to t-system depolarization- induced activation. The quantitative parameters assessed were the amplitude of the maximum depolarizationinduced force response (DIFRmax; normalized to the maximum Ca2-activated force in that fiber) and the number of responses elicited until the force declined by 75% of DIFRmax (R-D75%). The mean DIFRmax values for type IIB EDL and type IIB SM fibers were not statistically different, and both were greater than the mean DIFRmax for type I Sol fibers. The mean R-D75% for type IIB EDL fibers was greater than that for type I Sol fibers as well as type IIB SM fibers. These data suggest that E-C coupling characteristics of mechanically skinned rat single muscle fibers are related to MHCbased fiber type and the muscle of origin.
|Uncontrolled Keywords:||excitation-contraction coupling, myosin heavy chain, single muscle fiber, hybrid fiber|
|Subjects:||RFCD Classification > 210000 Science-General
RFCD Classification > 240000 Physical Sciences
Faculty/School/Research Centre/Department > School of Biomedical and Health Sciences
|Depositing User:||Ms Phung T Tran|
|Date Deposited:||17 Oct 2008 05:52|
|Last Modified:||19 Jul 2016 05:19|
|ePrint Statistics:||View download statistics for this item|
|Citations in Scopus:||14 - View on Scopus|
Repository staff only