[Activity of the skeletal muscle proteolytic systems during functional unloading].

The recovery of the skeletal muscle structure and function after prolonged disuse is the problem of the rehabilitation and space medicine great concern. Hypokinesia affects mainly the postural muscles responsible for the support reaction. Atrophy developed under disuse is the result of the protein synthesis and proteolysis balance shift. Several signaling systems regulating proteolysis are known now, though only recently researchers paid attention to the question whether these systems work identically in the muscles atrophied under different stimuli (denervation, starvation etc.). In this review we aimed to summarize and analyze cumulative data concerning the work of the different proteolytic systems during the atrophy caused by hypokinesia and/or hypogravity. Also we discuss here the latest data about the interconnection of the signaling systems regulating the structural and functional muscle proteins degradation and synthesis under disuse.