Wojciech Baran

Ultrastructural morphometric evaluation of muscles in pigeons kept under conditions of long-lasting hypodynamic state

Abstract The purpose of this research was to evaluate morphometrically the structure of muscles of pigeons in hypodynamic state, i.e., when they are deprived of flying. The pigeons were allowed to move freely in the cages, thus avoiding a stress reaction. The results of these investigations revealed, that in the 6 months following initiation of the experiment, marked changes appeared in the enzymatic reactions in the mitochondria of the muscle fibers. These changes were reflected in the accumulation of glycogen and fatty droplets. After 12 to 18 months there appeared a limitation of mobility of the muscles followed by an extensive atrophy of the myofibrils with a decreased volume of sarcomeres. The above changes may be interpreted as a consequence of lack of tissue oxygen, aberration in the catabolic pathways of carbohydrates, and diminished content of ATP necessary for proper metabolic functions.

Morphometric ultrastructural study of the regeneration of soleus muscle in hypokinesia

SummaryThe aim of the present study was a morphometric ultrastructural evaluation of regenerating soleus muscle fibers after denervation under conditions of hypokinesia. It was found that in rats kept under conditions of hypokinesia degenerative changes in the soleus muscle after denervation are more pronounced than in the control. On the 36th day after denervation of muscle, symptoms of regeneration of muscle fibers were observed. It was more pronounced in the control than in the experimental groups. Denervation and immobilization applied simultaneously causes more severe degeneration and atrophy of muscle fibers than does the action of only one of these factors.