Cytosolic free Ca2+ concentration is a key factor in pulmonary vasoconstriction and vascular remodeling of pulmonary artery smooth muscle cells (PASMC). These processes contribute to pulmonary arterial hypertension and are influenced by expression of calcium sensing receptor (CaSR). Although regulation of CaSR expression is precisely controlled, the contribution of microRNAs is incompletely understood. Here, we demonstrate that miR-429, miR-424-5p, miR-200b-3p, and miR-200c-3p regulate CaSR by

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... argeting specific 3'-UTR, suggesting that these miRNAs function as CaSR inhibitors in PASMC. Moreover, miR-429 and miR-424-5p inhibit proliferation of PASMC by downregulating CaSR, resulting in reduced Ca2+ influx under both normoxia and hypoxia. These findings indicate miR-429 and miR-424-5p target CaSR and may function as Ca2+ influx suppressors in pulmonary arterial hypertension-associated diseases.