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Updated: Aug 19, 2026

Assessment of Myofilament Ca2+ Sensitivity Underlying Cardiac Excitation-contraction Coupling
Published on: August 1, 2016
[Cardiac function involving the T-type Ca2+ channel]
Katsushige Ono1, Tae Seong Lee, Toshihiko Kaku
1Department of Cardiovascular Science, Oita Medical University.
Abstract:
Functional involvement of the T-type calcium channel in the heart excitation at the pathophysiological conditions has been elucidated. The T-type channel is classified as the low voltage-activated channel (LVA) solely in the voltage activated calcium channel. In 1998, Perez-Reyes and coworkers cloned the first LVA alpha(1) subunit, which was named as alpha(1G) or Ca(V)3.1. In the cardiac muscle, alpha(1G) and the other clone alpha(1H) are dominantly expressed in the sinoatrial node, atrioventricular node and other signal conduction tissues. Abnormal activity of T channels has been suggested in the following cardiovascular diseases: hypertension, cardiac hypertrophy, cardiac infarction. The cloning of the T-type calcium channel allows us to understand the function of the channel in detail and options for therapeutics in the T-type channel-related diseases.
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