title: Role of NO-synthase in regulation of protein metabolism of stretched rat m. soleus muscle during functional unloading.
abstract: Gravitational unloading causes atrophy of muscle fibers and can lead to destruction of cytoskeletal and contractile proteins. Along with the atrophic changes, unloaded muscle frequently demonstrates significant shifts in the ratio of muscle fibers expressing fast and slow myosin heavy chain isoforms. Stretching of the m. soleus during hindlimb suspension prevents its atrophy. We supposed that neuronal NO-synthase (NOS) (which is attached to membrane dystrophin-sarcoglycan complex) can contribute to maintenance of protein metabolism in the muscle and prevent its atrophy when m. soleus is stretched. To test this hypothesis, we used Wistar rats (56 animals) in experiments with hindlimb suspension during 14 days. The group of hindlimb suspended rats with stretched m. soleus was injected with L-NAME to block NOS activity. We found that m. soleus mass and its protein content in hindlimb-suspended rats with stretched m. soleus were preserved due to prevention of protein degradation. NOS is involved in maintenance of expression of some muscle proteins. Proliferation of satellite cells in stretched m. soleus may be due to nNOS activity, but maintenance of muscle mass upon stretching is regulated not by NOS alone.
authors.affiliation: Faculty of Basic Medicine, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Yu N
authors.initials: YN
authors.lastname: Lomonosova
authors.forename: G R
authors.initials: GR
authors.lastname: Kalamkarov
authors.forename: A E
authors.initials: AE
authors.lastname: Bugrova
authors.forename: T F
authors.initials: TF
authors.lastname: Shevchenko
authors.forename: N L
authors.initials: NL
authors.lastname: Kartashkina
authors.forename: E A
authors.initials: EA
authors.lastname: Lysenko
authors.forename: B S
authors.initials: BS
authors.lastname: Shenkman
authors.forename: T L
authors.initials: TL
authors.lastname: Nemirovskaya
mesh_terms: D000818:Animals; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D019417:Hindlimb Suspension; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism
chemical_list: D018841:HSP90 Heat-Shock Proteins; D009124:Muscle Proteins; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D044767:Ubiquitin-Protein Ligases; D019893:Ribosomal Protein S6 Kinases; C526901:Rps6kb1 protein, rat; D019331:NG-Nitroarginine Methyl Ester