SPATIAL PATTERNS OF FIBER TYPES IN ATROPHIED SKELETAL-MUSCLE

This study examined the spatial distributions of different fiber types in the soleus muscle of control rats and in rats subjected to hindlim b unloading for 28 days. The frequencies with which muscle fibers of o ne type were adjacent to each other and to fibers of other types were tabulated and compared to expectations generated from Monte Carlo simu lations. In the normal rat, there is a tendency for Type I fibers to a void adjacency with each other, a tendency that persisted in the hindl imb-suspended group, despite the substantial shrinkage in size of Type I fibers. We conclude that this treatment, unlike neurogenic patholog ies, does not cause any remodeling of the adjacency relations of fiber s.