Voltage-dependent Ca²⁺ channels (Ca_V channels) are pivotal players in many physiological roles such as secretion, contraction, migration and excitation.¹

The voltage-dependent Ca²⁺ channels are composed of several subunits; α1, β, α2δ and γ. Ca_V channels were originally divided into six physiological types: L-, N-, P-, Q-, R-, and T-type.

The Ca_V2.2 (formally named α1B) composes the α1 poreforming subunit for the N-type Ca²⁺ channel family. They are involved in neurotransmitter release from central neurons, including glutamate, γ-aminobutyric acid, acetylcholine, dopamine and noradrenaline.²

The Ca_V2.2 is expressed preferentially in the central nervous system, where along with Ca_V2.1, it is responsible for pre-synaptic Ca²⁺ influx and neurotransmitter release.^1,3

The Ca_V2.2 channel is negatively regulated by many different GPCRs. There are two ways that this is done: either by directly binding Gβγ to the channel or by an indirect mechanism involving second messenger and channel phosphorylation.⁴ 

ω-Conotoxin GVIA (#C-300) is a specific blocker of Ca_V2.2 Ca²⁺ channels. It specifically blocks N-type Ca_V channels by binding to the Ca_V2.2 α1 subunit (α1B) and its action is only partially reversible.^5,6