Delayed muscle soreness in man is known to be attributed to a disorganization of the
myofibrils. Our aim in the present study was to investigate whether the intermediate
filament system is affected as well. Biopsies were taken from the right m. vastus
lateralis of six males (aged 23 ± 3 years) suffering from severe post-exercise soreness
of their thigh muscles. Intermediate filament protein was visualized by indirect immunofluorescence
microscopy using an antibody specific to desmin. A typical finding in biopsies taken
3 days after exercise was abundant longitudinal “desmin” extensions. Moreover, strongly
autofluorescent granules were observed beneath the sarcolemma. It is concluded that
muscles subjected to unusual exercise contain myofibrillar and cytoskeletal disturbances
accompanied by increased lysosomal activity.
human - muscles - muscle soreness - immunocyto-chemistry - intermediate filaments
