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Updated: Aug 14, 2026

Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement
Published on: July 26, 2017
Skeletal muscle cells express different isoforms of the calcium channel alpha2/delta subunit
Thomas Nabhani1, Tanvi Shah, Jesús García
1Department of Physiology and Biophysics, University of Illinois at Chicago College of Medicine, 835 South Wolcott Avenue, Chicago, IL 60612, USA.
Abstract:
We examined developmental changes in calcium channel alpha2/delta subunit mRNA in skeletal muscle and their possible influence on L-type calcium currents (ICa-L). Several isoforms of alpha2/delta-1 mRNA were found in myotubes and muscle fibers, and their relative levels changed with time in culture or age of the animal. Levels of alpha2/delta-1a were largest in older myotubes and was the only alpha2/delta-1 isoform present in adult muscle. Both myotubes and muscle fibers also expressed low levels of alpha2/delta-2 and alpha2/delta-3 mRNA at all ages. alpha2/delta-4 mRNA could not be detected in either myotubes or muscle fibers. Changes in amplitude and voltage-dependent inactivation of the ICa-L concurred with the shift in alpha2/delta-1 isoform message, suggesting that alternative splicing of this subunit might be important for modulation of ICa-L.
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