Activators and inactivators of Ca++ channels: new perspectives

Recent advances in the pharmacology of voltage-operated Ca++ channels (VOCs) are reviewed. It is proposed that three subgroups of calcium-antagonists exist and the pharmacology of the "subgroups" is compared at the level of ligand binding and functional (in vitro and in vivo) experiments. Recent electrophysiological experiments have indicated that there may be two populations of VOCs. The implications of these findings are discussed in the light of the different antagonist subgroups.