TFRC and pulmonary arterial hypertension: In addition, Western blot analysis has demonstrated that PAH treatment downregulated the expression of GPX4 and SLC7A11, while upregulating the expression of transferrin receptor (TFRC), ferritin heavy chain (FTH1), and ferritin light chain (FTL), which are associated with intracellular Fe2+ regulation (Figures 5G,H).