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Updated: Aug 9, 2026

Analysis of Tubular Membrane Networks in Cardiac Myocytes from Atria and Ventricles
Published on: October 15, 2014
Tunicamycin inhibits the expression of surface Na+ channels in cultured muscle cells
Abstract:
We have investigated the effect of tunicamycin (TM), an inhibitor of protein glycosylation, on surface Na+ channels in cultured chick skeletal muscle cells. The expression of Na+ channels, estimated by the measurement of batrachotoxin (BTX)-activated 22Na+ uptake, was found to be significantly diminished after exposure of muscle cells to TM. This effect is partially reversed by the protease inhibitor leupeptin and is associated with a markedly enhanced rate of disappearance of Na+ channels from the surface of TM-treated cells. Our findings suggest that protein glycosylation contributes to the metabolic stability of voltage-sensitive Na+ channels.
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