Article
The biology and restorative capacity of long-term denervated skeletal muscle.
Basic and Applied Myology
(2002)
Abstract
Mammalian skeletal muscle undergoes profound atrophy after denervation. The functionalrestoration of denervated muscle is a significant clinical problem, and the success of restorativeattempts decreases substantially after several months of denervation. Rat extensordigitorum longus muscles are capable of excellent restoration for the first 2-3 months afterdenervation, but after that time the level of restoration upon reinnervation decreases dramatically.Severe atrophy precedes the loss of restorative capacity. Attempts to understandthe basis for the reduced restorative ability have led to an intensive analysis of the biologyof long-term denervated muscle. In fast muscles, the satellite cell population undergoes amajor increase over the first 2 months after denervation, and thereafter it steadily declines.Atrophying muscle fibers lose nuclei through apoptosis, and some degenerate. New musclefibers form either alongside atrophying muscle fibers or in place of degenerated ones. Themicrocirculation undergoes a tenfold diminution over the first year after denervation, andover time denervated muscle is characterized by increasing amounts of interstitial collagen.Various barriers to reinnervation are discussed. Attempts to improve the restoration oflong-term denervated muscle have included the stimulation of regeneration and removal ofinterstitial collagen. Both of these have resulted in significant improvement in the level offunctional restoration. Although chronic electrical stimulation maintains an excellent degreeof mass and force in a denervated muscle, grafts of such muscles undergo no better restorationthan grafts of denervated muscles.
Keywords
- denervation,
- regeneration,
- reinnervation,
- satellite cells,
- skeletal muscle,
- transplantation.
Disciplines
Publication Date
January 1, 2002
Citation Information
Bruce M. Carlson, Andrei B. Borisov, Eduard I Dedkov, Douglas E. Dow, et al.. "The biology and restorative capacity of long-term denervated skeletal muscle." Basic and Applied Myology Vol. 12 Iss. 6 (2002) p. 247 - 254 Available at: http://works.bepress.com/edward-dedkov/63/