As shown in Fig. 7, after CacyBP/SIP inhibition, the degree of muscularization of small pulmonary arterioles in flow-associated PAH rats increased, and was accompanied by higher RVHI and worse hemodynamics including elevated RVSP, PASP, and mPAP compared to that in the MCT-AV group. This evidence concerns the gene CACYBP and pulmonary arterial hypertension.