I report here the data concerning number and size of the skeletal muscle fibers. Muscular dystrephic white mice (Jax, 129 strain) and control mice were sacrificed at age fo 17, 29, and 53 weeks.
In the dystrophic mice the number of muscle fibers (Tibialis anterior and soleus muscle) ranged about 50% than less those in control mice.
The number of skeletal muscle fiibers in control mice was highest at 29 weeks, and lowest at 53 weeks. Contrary in muscular dystrophy the number of fibers did not fluctuate from 17 weeks through and including the 53rd week.
The diameter of cross-section´s of skeletal muscles was studied, and generally the diameter of dystrophic mucle fibers was smller than the control. The diameter of dystrophic mucle fibers was smaller than the control. The diameter of cross-section muscle fibers was largest at 29 weeks (31.35u) in control and 17 weeks, (26.96u) in muscular dystrophy.
The standard deviation of the diameter of muscle fibers was studied and we concluded that the highest standard deviation was in 17 week old dystrophic Tibialis anterior musele. Generally standard deviation was higher in muscular dystrophic group than those control group.
Conclusion of This Sludy
The total number of muscle fibers and the diameter of crossisectioned skeletal muscle fibers declined gradually from 17 weeks control mice through 29 weeks to 53 weeks. due to the natural phenomena of senility of the muscle tissue.
But in the dystrophic mice the number of the muscle fibers did not decrease, but slightly increased as a later age, which indicates that muscular dystrophic degenerative changes begins actually at a younger age (before 17 weeks), and after a certain age (29weeks), The progressive degenerative dystrphic phenmena seems to slow down, or even some fibers regenerate.
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