The T-type calcium channel is a type of voltage-gated calcium channel. "T" stands for transient referring to the length of activation. As with other sub-types of voltage-gated calcium channel, the α1 subunit is the one that determines most of the channel's properties. T-type calcium channels may contain one of three α1 subunits, α1G (Cav3.1), α1H (Cav3.2) or α1I (Cav3.3).

Along with sodium "funny current," the T-type calcium channel produces the pacemaker potential in the SA node of the heart. Similarly in the CNS, T-type calcium channels and H-type "funny current" cation channels contribute to tonic bursting activity in thalamus. and in low-threshold spikes.

T-type calcium channel blockers are used primarily as antiepileptics.

Pharmacological evidence suggests a role for T-type calcium channels in animal models of pulmonary hypertension

Pulmonary hypertension

In medicine, pulmonary hypertension is an increase in blood pressure in the pulmonary artery, pulmonary vein, or pulmonary capillaries, together known as the lung vasculature, leading to shortness of breath, dizziness, fainting, and other symptoms, all of which are exacerbated by exertion...

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