Synonyms:BIII, Brain calcium channel III, CACH5, CACNA1B, CACNL1A5, CACNN, Cav2.2 Background:Voltage-sensitive calcium channels(VSCC) mediate the entry of calcium ions into excitable cells and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, gene expression, cell motility, cell division and cell death. The isoform alpha-1B gives rise to N-type calcium currents. N-type calcium channels belong to the 'high-voltage activated'(HVA) group and are blocked by omega-conotoxin-GVIA(omega-CTx-GVIA) and by omega-agatoxin-IIIA(omega-Aga-IIIA). They are however insensitive to dihydropyridines(DHP), and omega-agatoxin-IVA(omega-Aga-IVA). Calcium channels containing alpha-1B subunit may play a role in directed migration of immature neurons.