[Neuronal NO-synthase as the molecular guard of myofiber stability. NO-dependent signaling pathways in the active and unloaded muscle].

The review is dedicated to the signaling pathways triggered by the nitric oxide II in skeletal muscle. Analysis of the current literature shows that during physical exercise of various intensity and regimen the nitric oxide is an essential trigger of the signaling pathways, leading to the alteration of the structural and metabolic myofiber profile and enhancement of its functional capacity. At the same time during the elevated muscle contractile activity (for instance, eccentric activity), NO serves as a protective and stabilizing agent, preventing from the intensification of the proteolytic processes.

[Effect of 30-day space flight and subsequent readaptation on the signaling processes in m. longissimus dorsi of mice].

Some steps of anabolic and catabolic signaling pathways were investigated in postural/tonic m. longissimus dorsi of mice following the 30-day orbital flight of biosatellite "Bion-M1" and 8-day recovery. Western blotting was used for determining insulin receptor substrate 1 (IRS-1) and AMR-activated protein kinase (AMPK) involved in reciprocal regulation of anabolic and catabolic pathways, as well as E3-ligase MURF-1, and elongation factor eEF2.

[Role of calcium-dependent mechanisms in the development of atrophy in postural muscle deprived of gravitational loading].

Downsizing of muscle fibers, decline of their contractility and alteration of the myosin phenotype towards fast isoforms prevalence are ranked among the main consequences of gravitational unloading of postural muscles. Role of Ca2+ ions in these processes is the subject of the article. Authors revealed increase in the Ca2+ content in myofibers of resting m.

[Expression of splice-variants of the insulin-like growth factor I and the condition of the cell-myosatellite pool in the rat m. soleus under conditions of gravitation relief and passive stretching].

We suggested that satellite proliferation with subsequent incorporation of their nuclei in the fibres was essential for enhancement of the protein synthesis in the rat relieved m. soleus. In passive stretch of the muscle, the number of labelled cells exceeded 2.

[Protective effect of nitric oxide on cytoskeletal proteins in skeletal muscles under eccentric exercise].

The protective effect of nitric oxide (NO) on the cytoskeletal muscle proteins desmin and dystrophin has been studied under eccentric exercise. Experiments were performed on 28 male Wistar rats, which were divided into four groups: cage control (C, n = 7); group of eccentric exercise (running down a motor-driven treadmill, inclination 16 degrees) (20 m/min, 40 min running) (R, n = 7); eccentric exercise + L-arginine group (RA, n = 7) (with a daily supplementation of 500 mg/kg wt L-arginine for 3 days before the running); and eccentric exercise + L-NAME group (RN, n = 7) (with a daily supplementation of 90 mg/kg wt L-NAME (Nomega-nitro-L-arginine methyl ester, nNOS blocker) for 3 days before the running). It was found that increasing the NO concentration (in RA group) prevents the disruption of the dystrophin layer and decreases the loss of desmin in m.