The alpha-2/delta subunit of voltage-dependent calcium channels regulates calcium current density and activation/inactivation kinetics of the calcium channel. Acts as a regulatory subunit for P/Q- type calcium channel (CACNA1A), N-type (CACNA1B), L-type (CACNA1C OR CACNA1D) but not T-type (CACNA1G) (By similarity). . This is the function of CACNA2D3 (calcium voltage-gated channel auxiliary subunit alpha2delta 3, Ensembl gene identifier ENSG00000157445).