Antagonist binding sites of voltage-dependent calcium channels

Voltage-dependent calcium channels are crucial targets for a wide range of clinically active small organic pharmacological agents. These agents fall into several distinct classes of blockers, each associated with a unique site on the calcium channel α1 subunit. In addition, a number of peptide toxins isolated from invertebrates specifically bind to and block certain subtypes of voltage-dependent calcium channels. Voltage-dependent calcium channels are comprised of multiple subtypes, and not each of those subtypes are equally sensitive to small organic compounds and peptide blockers. Here, I present an overview of the classes of calcium channel blockers and our current understanding of their sites of action on the calcium channel protein. Drug Dev. Res. 42:131–143, 1997.