STIM2 (Stromal Interaction Molecule 2)-Mediated Increase in Resting Cytosolic Free Ca²⁺ Concentration Stimulates PASMC Proliferation in Pulmonary Arterial Hypertension.

ABSTRACT: An increase in cytosolic free Ca²⁺ concentration ([Ca²⁺]_cyt) in pulmonary artery smooth muscle cells (PASMCs) triggers pulmonary vasoconstriction and stimulates PASMC proliferation leading to vascular wall thickening. Here, we report that STIM2 (stromal interaction molecule 2), a Ca²⁺ sensor in the sarcoplasmic reticulum membrane, is required for raising the resting [Ca²⁺]_cyt in PASMCs from patients with pulmonary arterial hypertension (PAH) and activating signaling cascades that stimulate PASMC proliferation and inhibit PASMC apoptosis. Downregulation of STIM2 in PAH-PASMCs reduces the resting [Ca²⁺]_cyt, whereas overexpression of STIM2 in normal PASMCs increases the resting [Ca²⁺]_cyt

SUBMITTER: Song S 

PROVIDER: S-EPMC5955710 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature