Identification of a approximately 170K subunit of the cardiac calcium channel using a monoclonal antibody to the skeletal muscle dihydropyridine receptor.

Our newly isolated monoclonal antibody (#78) specifically interacts with the 170Kd 1,4 dihydropyridine binding component of the skeletal muscle calcium channel. Dihydropyridine receptor (DHPR) from rabbit skeletal muscle and canine cardiac membranes were purified by monoclonal antibody #78 affinity chromatography. We show that DHPR from canine cardiac membranes like DHPR from rabbit skeletal membranes contain a approximately 170Kd polypeptide to which antibody #78 immunoblots under both reducing and non-reducing conditions.