ITGB3 and pulmonary arterial hypertension: After approximately 4 weeks, the mPAP and RVSP levels of rats injected with MCT were decreased by the overexpression of miR‐223‐3p or the silencing of ITGB3. The staining results revealed that both miR‐223‐3p overexpression and ITGB3 knockdown alleviated the pulmonary vascular remodelling and improved the PAH pathological features of rats.