Single skeletal muscle fiber elastic and contractile characteristics in young and older men
2007 (English)In: The journals of gerontology. Series A, Biological sciences and medical sciences, ISSN 1079-5006, E-ISSN 1758-535X, Vol. 62, no 4, 375-381 p.Article in journal (Refereed) Published
The current investigation was designed to: (a) assess the impact of aging on elastic characteristics of single skeletal muscle fibers from young (N = 6) and older men (N = 6); and (b) correlate the potential changes, with the fiber contractile properties. Chemically skinned single muscle fibers (n = 235) from vastus lateralis muscle were maximally activated. Maximal force and cross-sectional area were measured, and specific force calculated. The slack test was used to measure maximal unloaded shortening velocity. A quick release of 0.15% of fiber length was applied to determine instantaneous stiffness. The myosin heavy chain isoform composition of each single fiber was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Aging induces changes in both fiber elasticity (i.e., increased instantaneous stiffness) and contractility (i.e., reduced specific force and unloaded shortening velocity) in type I and IIa fibers. However, the changes in fiber stiffness may not directly influence contractile characteristics alterations.
Place, publisher, year, edition, pages
2007. Vol. 62, no 4, 375-381 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-143004ISI: 000250763400006PubMedID: 17452730OAI: oai:DiVA.org:uu-143004DiVA: diva2:389017