All L-type calcium channels are encoded by one of the CaV1 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.
Several peptidyl toxins are described that are specific L-type channels blockers, but so far no selective blocker for one of the CaV1 isoforms have been described. These include the Mamba toxins Calcicludine (#C-650), Calciseptine (#C-500) and FS-2 (#F-700).
All CaV1 channels are influenced by dihydropyridines (DHP) and are also referred to as DHP receptor. While the CaV1.1 and CaV1.4 isoforms are expressed in restricted tissues (skeletal muscle and retina, respectively), CaV1.3 channels are found in heart, brain and pancreas and CaV1.2 channels are ubiquitously expressed.
There are two splice variants to the Cav1.2 channel designated Cav1.2a and Cav1.2b. The expression of the Cav1.2b variant is restricted to smooth muscle while Cav1.2a specifically expressed in cardiac muscle.
