[The effect of support loads and CNS stimulants on the development of the atrophic process in the muscles of suspended rats].

The histomorphometric method there was used to study effects of ephedrine, strychnine, and support loads on the atrophy of m. soleus and m. gastrocnemius in rats with load-deprived lower extremities (14-day tail-suspension). Deficiency of support loads on the lower extremities led to atrophy of the muscles, especially the slow m. soleus. Injections of ephedrine (0.06 mg/kg), strychnine (0.015 mg/kg) as well as ephedrine and strychnine at one and the same time did not affect the development of atrophy. On the contrary, daily 2-hr support loading of the rear extremities had a favourable effect on the muscle atrophy as it was slowed down. Particularly effective were injections of ephedrine on the background of support loads following which the mass of m. soleus in the suspended rats was close to vivarium control. It is suggested that the preventive effect of ephedrine is associated with stimulating the CNS controllers of the somatotropic function of the pituitary body and eventual enhancement of the somatotropic hormone production.