All L-type calcium channels are encoded by one of the Ca_V1 channel genes. These channels play a major role as a Ca²⁺ entry pathway in skeletal, cardiac and smooth muscles as well as in neurons, endocrine cells and possibly in non-excitable cells such as hematopoetic and epithelial cells. All Ca_V1 channels are influenced by dihydropyridines (DHP) and are also referred to as DHP receptors.

While the Ca_V1.1 and Ca_V1.4 isoforms are expressed in restricted tissues (skeletal muscle and retina, respectively), the expression of Ca_V1.2 is ubiquitous and Ca_V1.3 channels are found in the heart, brain and pancreas. Several peptidyl toxins are described that are specific L-type channel blockers, but so far no selective blocker for one of the Ca_V1 isoforms have been described. These include the Mamba toxins Calcicludine (#SPC-650), Calciseptine (#C-500) and FS-2 (#F-700).