Administration of the apelin peptide (Alastalo et al., 2011; Falcão‐Pires et al., 2009) or other agents stimulating apelin expression (Bertero et al., 2014; Nickel et al., 2015; Spiekerkoetter et al., 2013) or downstream mediators of the apelin pathway (Kim et al., 2013) has demonstrated benefits in animal models of PAH. This evidence concerns the gene APLN and pulmonary arterial hypertension.