The increase in endocytosis of mouse skeletal muscle after denervation and the proliferation of satellite cells

The relationship between increase of endocytosis and proliferation of satellite cellsin mouse skeletal muscle was studied by biochemical and culture methods in intro. The results indicated that: (1) 4 d or 6 d after denervation, increase of endocyto--sis and proliferation of satellite cells in denervated muscle were induced. (2) Actino--mycin D inhibited activation of satellite cells and endocytosis in normal muscle. (3)While in denervated muscle, actinomycin D inhibited proliferation of satellite cells aswell as increase of endocytosis, but could not prevent muscle atrophy after denerva-tion. These results imply that proliferation of satellite cells and increase of endocytosisin the muscle may concur to the appearance of some factors after denervation, or in-crease in endocytosis is a mere result of proliferation of satellite cells.