[Effect of space flight factors on rat skeletal musculature]

Morphological and histochemical examinations of skeletal muscles of flight rats demonstrated atrophic and dystrophic developments in M. soleus which were followed by metabolic disorders in the muscular tissue. The changes were reversible, although they did not disappear entirely on the 27th postflight day. Early signs of atrophic developments were found in M. gastrocnemius, M. quadriceps, M. extensor digitorum longus and M. biceps brachii on the 2nd postflight day. The comparative study of the data obtained from flight and ground-based synchroneous rats showed that muscular pathologies developed as a result of hypodynamics and were enhanced by weightlessness-effects.