Cav2sarja

Cav2sarja, or the Cav2 series, refers to the Cav2 subfamily of voltage-gated calcium channels. These channels are responsible for rapid calcium entry into presynaptic terminals in response to membrane depolarization, a key trigger for fast neurotransmitter release. The term Cav2 is commonly used in English-language neuroscience, while Cav2-sarja is the Finnish designation found in some scientific literature.

The Cav2 family comprises three pore-forming α1 subunits: Cav2.1, Cav2.2, and Cav2.3. Each α1 subunit is encoded by a separate gene (CACNA1A for Cav2.1, CACNA1B for Cav2.2, and CACNA1E for Cav2.3) and assembles with auxiliary subunits such as beta and alpha2delta that influence trafficking, localization, and channel kinetics. Structural features include four homologous domains with voltage-sensing segments and a selectivity filter that favors calcium ions.

Functionally, Cav2 channels are highly expressed in the nervous system and are concentrated at presynaptic terminals. Cav2.1 (P/Q-type) channels are prominent in the cerebellum and contribute to precise timing of neurotransmission, while Cav2.2 (N-type) channels are important in pain pathways and autonomic circuits. Cav2.3 (R-type) channels provide additional presynaptic calcium signals in various brain regions and retina. Their activity is tightly regulated by voltage, calcium-dependent feedback, and signaling pathways that modulate neurotransmitter release.

Clinical relevance includes associations between CACNA1A mutations and disorders such as familial hemiplegic migraine and episodic ataxia type 2, as well as other cerebellar ataxias. Cav2.2 channels are targets for analgesics derived from conotoxins, and pharmacological modulation of Cav2 channels remains an area of interest for treating chronic pain and certain neurological conditions.