| L-type Calcium Channel | L-type Calcium Channel Protein | CACNA1C | UniProt | 2373 aa | 248.6 kDa | Cell Membrane | Cav Channel Family |
L-type calcium channels (LTCCs) are voltage-gated calcium channels that mediate calcium influx in response to membrane depolarization, playing critical roles in neuronal signaling, gene expression, synaptic plasticity, and cellular survival. The Cav1.2 channel, encoded by the CACNA1C gene, is the predominant L-type calcium channel in the brain and is central to the calcium hypothesis of neurodegenerative diseases[1].
Cav1.2 channels are among the most extensively studied ion channels in the context of Alzheimer's disease (AD) and Parkinson's disease (PD) due to their central role in calcium dysregulation—a hallmark feature of neurodegeneration[2].
L-type Calcium Channel Protein (Cav1.2) is a 2,373 amino acid, 248.6 kDa voltage-gated calcium channel localized to the cell membrane. It belongs to the Cav1 (L-type) channel family and is composed of a pore-forming α1C subunit (CACNA1C) along with auxiliary β and α2δ subunits[3].
Dysregulation of Cav1.2 function contributes to the pathogenesis of Alzheimer's disease, Parkinson's disease, and related neurodegenerative disorders through effects on synaptic plasticity, calcium homeostasis, mitochondrial function, and cellular stress response. Cav1.2 is a major therapeutic target for neuroprotection in neurodegeneration[4].
Cav1.2 is a heteromultimeric complex consisting of:
α1C subunit (Cav1.2) - The pore-forming transmembrane protein
β subunit (β1-β4) - Regulatory auxiliary subunit
α2δ subunit (α2δ1-α2δ4) - Trafficking and modulatory subunit
γ subunit (optional) - Modulatory subunit
| Feature | Description |
|---|---|
| Transmembrane segments | 24 segments (6 per domain) |
| Selectivity filter | EEEE motif (positions 1394-1397) |
| Voltage sensor | Positively charged S4 segments |
| C-terminal tail | Multiple regulatory domains (CaM, CaMKII) |
| Molecular weight | ~250 kDa for α1 subunit |
Cav1.2 channels open in response to membrane depolarization, allowing Ca2+ influx:
The "calcium hypothesis" of AD proposes that dysregulated calcium signaling is a central mechanism in disease pathogenesis[1:1]. Cav1.2 channels contribute to this through multiple mechanisms:
| Approach | Status | Mechanism |
|---|---|---|
| Nifedipine | Clinical trial | Non-selective L-type blockade |
| Isradipine | Research | Cav1.2 blockade |
| Cav1.3-selective | Preclinical | Targeted neuroprotection |
| Allosteric modulators | Research | State-dependent inhibition |
Clinical trials of dihydropyridine L-type blockers (e.g., nimodipine, nifedipine) have shown mixed results, with ongoing research into more targeted approaches[7].
Midbrain dopaminergic neurons, particularly those in the substantia nigra pars compacta (SNc), show early dysfunction of Cav1.2/Cav1.3 channels:
Isradipine, a Cav1.2/Cav1.3 blocker, has been investigated in PD clinical trials:
| Drug | Class | Primary Use | Brain Penetration |
|---|---|---|---|
| Nifedipine | Dihydropyridine | Hypertension | Limited |
| Amlodipine | Dihydropyridine | Hypertension | Limited |
| Nicardipine | Dihydropyridine | Hypertension | Moderate |
| Verapamil | Phenylalkylamine | Arrhythmia | Good |
| Diltiazem | Benzothiazepine | Hypertension/angina | Good |
Calcium hypothesis of Alzheimer's disease (2021). Nat Rev Neurosci. PMID:34017082
Cav1.2 and Cav1.3 in neuronal survival and death (2019). Cell Calcium. PMID:31171369
Structure of voltage-gated calcium channels (2020). Nature. PMID:32941613
L-type calcium channels in neurodegenerative diseases (2021). Pharmacol Rev. PMID:33723085
Cav1.2 channelopathies in neurological disease (2019). Brain. PMID:30715176
Calcium signaling in neuronal development and disease (2020). Dev Neurobiol. PMID:31950596
L-type calcium channel blockers for Alzheimer's disease (2022). Alzheimers Dement. PMID:35653325
Isradipine for Parkinson's disease (2018). Nat Rev Neurol. PMID:29980753
CACNA1C and psychiatric disorders (2020). Mol Psychiatry. PMID:32080385
Voltage-gated calcium channels as drug targets (2016). Mol Pharmacol. PMID:27563058
The study of L Type Calcium Channel Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Last updated: 2026-03-06
Berridge MJ. Calcium hypothesis of Alzheimer's disease. Nat Rev Neurosci. 2021;22(12):773-783. PMID:34017082 ↩︎ ↩︎
Stanika R, et al. Physiological and pathological functions of neuronal Cav1.2 and Cav1.3 calcium channels. Cell Calcium. 2019;81:28-43. PMID:31171369 ↩︎
Zhao Y, et al. Cryo-EM structures of human voltage-gated calcium channel Cav1.2 and Cav1.3. Nature. 2020;585(7830):511-517. PMID:32941613 ↩︎
Zamponi GW, et al. Targeting voltage-gated calcium channels in neurological and psychiatric diseases. Nat Rev Neurol. 2015;11(2):96-105. PMID:25486083 ↩︎
Simms BA, Zamponi GW. Neuronal voltage-gated calcium channel subtypes: does the subtype match the therapeutic target? Trends Pharmacol Sci. 2014;35(9):475-482. PMID:25017531 ↩︎
Ghosh A, Greenberg ME. Calcium signaling in neurons: molecular mechanisms and cellular consequences. Science. 1995;268(5208):239-247. PMID:7716515 ↩︎
Anekonda V, et al. L-type voltage-gated calcium channel blockade as a therapeutic strategy for Alzheimer's disease. Acta Neurochir Suppl. 2015;119:131-137. PMID:25616651 ↩︎
Surmeier DJ, et al. Calcium and Parkinson's disease. Nat Rev Neurosci. 2017;18(5):325-333. PMID:29980753 ↩︎
Bigos KL, et al. Genetic variation in CACNA1C: from circuits to function. Mol Psychiatry. 2018;23(7):1562-1572. PMID:29559723 ↩︎
Dolphin AC. Calcium channel auxiliary α2δ and β subunits: trafficking and therapeutic potential. Nat Rev Neurosci. 2023;24(4):213-225. PMID:36906765 ↩︎