L-type voltage-gated calcium channel alpha-1 subunit (Cav1.x alpha-1 subunit (subtypes include Cav1.1, Cav1.2, Cav1.3, Cav1.4))

The L-type voltage-gated calcium channel alpha-1 subunit is the principal pore-forming component of the L-type calcium channel complex, which mediates high-voltage activated, long-lasting calcium influx in response to membrane depolarization[1][5][7][8]. There are four major human isoforms (Cav1.1, Cav1.2, Cav1.3, Cav1.4), encoded by genes such as CACNA1S, CACNA1C, CACNA1D, and CACNA1F respectively[5][8]. The alpha-1 subunit itself consists of four homologous domains, each containing six transmembrane helices, and harbors the channel's voltage sensor, ion-conducting pore, and major drug-binding sites[1][5][7]. These channels are essential for muscle contraction, cardiac rhythm regulation, synaptic transmission, and hormone secretion, and are a key therapeutic target for several cardiovascular and neurological conditions[1][3][5][7][8]. Mutations or dysregulation of the alpha-1 subunit (e.g., CACNA1C) are implicated in diseases such as arrhythmia, psychiatric disorders, and rare channelopathies[3][6][8]. Pharmacological antagonists (such as dihydropyridines, verapamil, and diltiazem) target this subunit to treat hypertension, cardiac arrhythmias, and related disorders[3][6][8].

Other names

L-type calcium channel alpha-1 subunitCav1.x (where x = 1–4, e.g., Cav1.2, Cav1.3)Voltage-dependent L-type calcium channel subunit alpha-1Dihydropyridine receptor alpha-1 subunit (DHP receptor)Voltage-gated calcium channel alpha-1 subunitGene/protein synonyms (for Cav1.2): CACNA1C, CACH2, CACN2, CACNL1A1, CCHL1A1[8]

Blockade of voltage-gated calcium influx via direct binding to alpha-1 subunit of L-type channel[1][3] Modulation of channel gating dynamics and inactivation/recovery[3] Inhibition of excitation-contraction coupling in muscle and reduction of cellular excitability[1][3][7]