Relative resistance to dystrophy of slow skeletal muscle of the mouse

Publisher Website
Google Scholar
Abstract
In mice with muscular dystrophy the percentage reduction in weight of the soleus was only 1/2 that of the gastrocnemius. Dystrophy did not change the ratio of soleus muscle to animal weight, but halved the ratio of gastrocnemius muscle to animal weight. Dystrophy reduced tension output about equally in both muscles, but shortened active-state plateau duration 20% in soleus and 42% in gastrocnemius. It did not affect soleus half-relaxation time but doubled it in gastrocnemius. During 600 1/sec twitches normal and dystrophlc soleus tensions declined by 30 and 26% of starting tension, respectively, compared to 94 and 43% in the corresponding gastrocnemli. Half-relaxation times shortened in normal and dystrophic soleus and dystrophic gastrocnemius, but lengthened in normal gastrocnemius. During 60 tetanl and 1/10 sec. soleus tensions remained unchanged, whereas tensions of normal and dystrophic gastrocnemii declined by 81 and 46%, respectively. The percentage increase in twitch tension caused by NO3 was equal in both soleus muscles, and tetani remained unaffected. Dystrophy affected soleus less severely than gastrocnemius muscle.