L-type voltage-gated calcium channels and N-type voltage-gated calcium channels (LTCC and NTCC)

L-type and N-type voltage-gated calcium channels (VGCCs) are essential transmembrane proteins that facilitate the entry of calcium ions into cells upon membrane depolarization. L-type channels (Cav1 family) are primarily expressed in cardiac and smooth muscle, where they are fundamental to excitation-contraction coupling and the regulation of vascular tone [UniProt, 2024]. N-type channels (Cav2.2) are predominantly located at presynaptic terminals in the nervous system, where they trigger the release of neurotransmitters such as glutamate and substance P, playing a vital role in pain signaling and sympathetic activity [PubMed, 2022]. While L-type blockers like dihydropyridines are standard treatments for hypertension and angina, N-type inhibitors like ziconotide are used for refractory chronic pain. Dual blockers, such as cilnidipine, target both channel types to provide antihypertensive effects while simultaneously suppressing sympathetic overactivity, potentially offering superior organ protection compared to L-type selective agents [PubMed, 2021].

Other names

Cav1 and Cav2.2 channelsHigh-voltage activated calcium channelsDihydropyridine-sensitive and Omega-conotoxin-sensitive calcium channelsHVA calcium channels

Inhibition of calcium ion influx through the pore-forming alpha-1 subunits (Cav1.x and Cav2.2) of voltage-gated calcium channels, leading to reduced smooth muscle contraction and decreased presynaptic neurotransmitter release [StatPearls, 2023; IUPHAR/BPS Guide to Pharmacology].