Acetylcholine sensitivity in replicating satellite cells.

Mononucleate myogenic cells lying within skeletal muscle fiber endomysium, the so-called satellite cells (SC), isolated from adult leg muscle of normal or dystrophic mice were studied by electrophysiological techniques. Normal SC responded to iontophoretic acetylcholine (ACh) by depolarization even during the replicative phase. Acetylcholine sensitivity increased after cell fusion. Replicating SC from dystrophic muscle did not exhibit any sensitivity to ACh, and neither did embryonic myoblasts.