title: Remodeling of the cytoskeletal lattice in denervated skeletal muscle.
abstract: The effect of denervation-induced atrophy on the cytoskeletal lattice in rat fast- and slow-twitch skeletal muscle has been investigated. Immunochemical analyses and immunofluorescence microscopy experiments employing monospecific antibodies to dystrophin, desmin, and alpha-tubulin were carried out on intact and denervated muscles. The relative cellular content of dystrophin and desmin were reduced in the soleus muscle (slow-twitch), while significant increases were shown in the gastrocnemius muscle (fast-twitch). In both muscles, alpha-tubulin levels increased up to 12-fold as a function of time compared to control values. Immunofluorescence microscopy revealed a distinct rearrangement of the microtubule network toward a predominantly longitudinal alignment, which was accompanied by an increase in the density of the fluorescence. It is concluded that the relative increase of the three structural proteins in the fast-twitch gastrocnemius muscle may be related to the apparent resistance of this muscle type to denervation-induced atrophy. The increased alpha-tubulin content in denervated slow- and fast-twitch muscles could be indicative of an adaptive mechanism designed to maintain the integrity of the muscle fiber in view of eventual regenerative activities.
authors.affiliation: Laval University Hospital Research Center, Québec, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Boudriau
authors.forename: C H
authors.initials: CH
authors.lastname: Côté
authors.forename: M
authors.initials: M
authors.lastname: Vincent
authors.forename: P
authors.initials: P
authors.lastname: Houle
authors.forename: R R
authors.initials: RR
authors.lastname: Tremblay
authors.forename: P A
authors.initials: PA
authors.lastname: Rogers
mesh_terms: D000818:Animals; D003599:Cytoskeleton / Q000502:physiology* / Q000648:ultrastructure; D003714:Denervation; D003893:Desmin / Q000378:metabolism; D016189:Dystrophin / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D007120:Immunochemistry; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000648:ultrastructure; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism; D018657:Muscle Fibers, Slow-Twitch / Q000378:metabolism; D018482:Muscle, Skeletal / Q000294:innervation* / Q000502:physiology* / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D014404:Tubulin / Q000378:metabolism
chemical_list: D003893:Desmin; D016189:Dystrophin; D014404:Tubulin