先天性筋ジストロフィー生検筋にみられるsatellite細胞の電子顕微鏡的研究

抄録

The satellite cell, a mononucleated cell enclosed within the striated muscle fiber, has been considered to be an origin of myoblasts in the myogenesis during the fetal development or in the course of skeletal muscle regeneration. As many authors have pointed out, satellite cells increasing in number are observed in many muscle diseases including the muscular dystrophy, espescially in young children.
The present paper deals with the distribution and the fine structural appearances of satellite cells in the muscles of three cases of congenital muscular dystrophy (CMD) (case 1: benign CMD, case 2: Ullrich-type CMD, case 3: Fukuyama-type CMD). In a biopsied muscle obtained from case 1, very striking features are the presence of myoblasts and of numerous satellite cells amounting to about 30% in the number of muscle fibers.
These satellite cells are rich in ribosomes and endoplasmic reticulum, which suggest the presence of the activity of myoblast formation. In the muscles of cases 2 and 3, on the other hand, the satellite cells contain only a few cell organelles although they are observed in a relatively large number. The satellite cells in the muscle of case 3 show a certain degree of regressive changes along with muscle fiber degeneration.
It is net fully clarified in this report, whether the presence of many satellite cells in the muscles of CMD manifests the muscle regeneration or the maturation arrest of fetal muscle.