GJA1 and idiopathic pulmonary arterial hypertension: In addition, studies have been reported that Cx43 expression was increased in rat pulmonary artery fibroblasts (rPAFs) and pulmonary arteries (PAs) from chronic hypoxia‐induced pulmonary hypertension patients, but decreased in PAs from idiopathic pulmonary arterial hypertension (IPAH) patients and rat pulmonary artery smooth muscle cells (rPASMCs).20, 31