Abstract
Desmin content and immunohistochemical appearance were measured in tibialis anterior muscles of rats subjected to a single bout of 30 eccentric contractions (ECs). Ankle torque was measured before EC and at various recovery times, after which immunohistochemical and immunoblot analyses were performed. Torque decreased by ∼50% immediately after EC and fully recovered 168 h later (P < 0.001). Loss of desmin staining was maximal 12 h after EC and recovered by 72 h. Immunoblots unexpectedly demonstrated a significant increase in the desmin-to-actin ratio by 72 h after EC (P < 0.01) and was still increasing after 168 h (P < 0.0001). These data demonstrate a relatively rapid qualitative loss of desmin immunostaining immediately after a single EC bout but a tremendous quantitative increase in desmin content 72-168 h later. This dynamic restructuring of the muscle's intermediate filament system may be involved in the mechanism of EC-induced muscle injury and may provide a structural explanation for the protective effects observed in muscle after a single EC bout.
Original language | English (US) |
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Pages (from-to) | R958-R963 |
Journal | American Journal of Physiology - Regulatory Integrative and Comparative Physiology |
Volume | 283 |
Issue number | 4 52-4 |
DOIs | |
State | Published - Oct 2002 |
Keywords
- Biomechanics
- Calpain
- Cytoskeleton
- Intermediate filaments
- Muscle injury
ASJC Scopus subject areas
- General Medicine