title: Influence of overload on phenotypic remodeling in regenerated skeletal muscle.
abstract: We studied the effects of 10 wk of functional overload on the expression of myosin heavy chain (MHC), sarcoplasmic reticulum Ca(2+)-ATPase isoforms (SERCA), and the activity of several metabolic enzymes in sham and regenerated plantaris muscles. Overload was accomplished by bilateral surgical ablation of its synergists 4 wk after right plantaris muscles regenerated after myotoxic infiltration. The overload-induced muscle enlargement was slightly less in regenerated than in sham muscles [28% (P < 0.005) and 43% (P < 0.001), respectively]. Overload led to an increase in type I MHC expression (P < 0.01) to a similar extent in sham and regenerated plantaris, while the expected shift from type IIb to type IIa MHC was less marked in regenerated than in sham plantaris. The overload-induced decrease in the expression of the fast SERCA isoform and in the activity of the M subunit of lactate dehydrogenase occurred to a similar extent in sham and regenerated plantaris [66% (P < 0.01) and 27% (P < 0.005), respectively]. In conclusion, the lesser responses of muscle mass and fast MHC composition of regenerated plantaris to mechanical overload suggest an alteration of the transcriptional, translational, and/or posttranslational control of gene expression in regenerated muscle.
authors.affiliation: Unité de Bioénergétique et Environnement, Centre de Recherches du Service de Santé des Armées, La Tronche, France. BIGARDXavier@compuserve.com
authors.forename: A X
authors.initials: AX
authors.lastname: Bigard
authors.forename: J
authors.initials: J
authors.lastname: Zoll
authors.forename: F
authors.initials: F
authors.lastname: Ribera
authors.forename: P
authors.initials: P
authors.lastname: Mateo
authors.forename: H
authors.initials: H
authors.lastname: Sanchez
authors.forename: B
authors.initials: B
authors.lastname: Serrurier
authors.forename: R
authors.initials: R
authors.lastname: Ventura-Clapier
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D002950:Citrate (si)-Synthase / Q000378:metabolism; D003402:Creatine Kinase / Q000378:metabolism; D004546:Elapid Venoms / Q000633:toxicity; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D009135:Muscular Diseases / Q000139:chemically induced / Q000473:pathology; D018995:Myosin Heavy Chains / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects / Q000502:physiology; D010641:Phenotype; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000187:drug effects / Q000502:physiology*; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases
chemical_list: D004546:Elapid Venoms; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D002950:Citrate (si)-Synthase; D003402:Creatine Kinase; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D018995:Myosin Heavy Chains; D000252:Calcium-Transporting ATPases