L-type voltage-dependent calcium channel (LTCC) (LTCC)

L-type voltage-dependent calcium channels (LTCCs) are members of the voltage-gated ion channel superfamily, primarily responsible for the influx of calcium ions into excitable cells in response to membrane depolarization [1: Catterall WA, Cold Spring Harb Perspect Biol, 2011]. These channels are characterized by their high-voltage activation threshold and long-lasting (L-type) conductance, playing a pivotal role in excitation-contraction coupling in cardiac and smooth muscle, as well as hormone secretion and gene expression [2: Striessnig J, et al., Trends Pharmacol Sci, 2014]. The LTCC family includes four subtypes: Cav1.1, Cav1.2, Cav1.3, and Cav1.4, with Cav1.2 being the predominant isoform in the heart and vasculature [3: Zamponi GW, et al., Pharmacol Rev, 2015]. Dysfunction or overactivity of LTCCs is implicated in various cardiovascular diseases, such as hypertension and arrhythmias, as well as neuropsychiatric disorders [4: Berger SM, et al., Cell Tissue Res, 2018]. Consequently, LTCCs are major therapeutic targets for calcium channel blockers (CCBs), including dihydropyridines, phenylalkylamines, and benzothiazepines, which are widely used to manage blood pressure and heart rate [5: StatPearls, Calcium Channel Blockers, 2023].

Other names

Cav1 channelDihydropyridine-sensitive calcium channelHigh-voltage activated calcium channelCACNA1SCACNA1CCACNA1DCACNA1FVoltage-gated calcium channel subunit alpha1SVoltage-gated calcium channel subunit alpha1CVoltage-gated calcium channel subunit alpha1DVoltage-gated calcium channel subunit alpha1F

Drugs targeting L-type calcium channels primarily act as antagonists (blockers) that bind to the alpha-1 subunit of the channel complex. This binding inhibits the inward flow of calcium ions into excitable cells during membrane depolarization. In vascular smooth muscle, this reduction in intracellular calcium leads to relaxation and vasodilation; in cardiac muscle, it results in reduced contractility (negative inotropy) and slowed electrical conduction through the atrioventricular node [5: StatPearls, Calcium Channel Blockers, 2023].