Effects of chronic ouabain treatment on [3H]ouabain binding sites and electrogenic component of membrane potential in cultured rat myotubes.

The effects of incubation of cultured rat skeletal myotubes in ouabain were studied on the number of [3H]ouabain binding sites and electrogenic component of membrane potential. Ouabain treatment for 2-6 days increased the number of binding sites, resting membrane potential (Em) and the ouabain-sensitive component of Em in the muscle cells. The findings strengthen the idea that Na,K-ATPase has an important role in regulation of Em in cultured skeletal muscle and suggest that Na-K pump inhibition during development may be a regulatory mechanism for cellular synthesis of Na,K-ATPase.