Calcium-sensing receptor (CaSR) (CaSR)

The Calcium-sensing receptor (CaSR) is a G protein-coupled receptor expressed in vascular tissues including perivascular nerves, vascular smooth muscle cells (VSMCs), and endothelial cells, where it senses extracellular calcium levels to regulate vascular function. Activation of CaSR by elevated extracellular calcium induces vasodilatation via perivascular nerves and endothelial cells through release of vasoactive substances, IKCa channel stimulation, nitric oxide synthesis, and downstream activation of BKCa and KATP channels in VSMCs. In VSMCs, CaSR stimulation promotes vasoconstriction through Gq/11-coupled increases in intracellular calcium, calmodulin kinase II activation, and phospholipase A2 signaling. Beyond contractility, CaSR influences VSMC proliferation and calcification, contributing to vascular remodeling. Dysregulated CaSR activity is implicated in cardiovascular diseases such as hypertension, pulmonary arterial hypertension, and atherosclerosis, positioning calcimimetics (activators) and calcilytics (inhibitors) as potential therapeutic agents to modulate blood pressure and prevent calcification. "Vascular calcium" is not a specific molecular target but a misnomer likely referring to calcium ions or related processes in vascular signaling.

Other names

Calcium-sensing receptor

Gq/11 protein-coupled pathway activation leading to vasoconstriction, Activation of IKCa channels and nitric oxide synthesis for vasodilatation, Regulation of proliferation and calcification in vascular smooth muscle cells