What is repair of skeletal muscle?
Answer:
skeletal muscle cells ar long multinucleated, permanent cells
myonuclei ar unable to divide
1. macrophages clean up intracelular debris
2. satellite cells, mitosis --> myoblasts --> migrate from marginal site to centre of myobibrils, new myofiber nuclei
3. intact basal lamina: keeps both satellite cells and their myoblast progeny within damaged segment, keeps fibroblasts out, allows entry and exit of macorphages
4. after critical mass of myoblasts have formed they begin to fuse to form myotubular giant cells
5. myotubes sent out numerous cytoplasmic processes of which re-establish contact with the original muscle cell
6. cell membranes fuse to facilitat union of regenerated segment with vable myofibre