TsIIA plays a protective role by inhibiting strain-induced endothelin-1 (ET-1) expression, increasing the endothelin type B (ETB) receptors, reducing the ETA receptors, upregulating eNOS, and increasing the formation of NO during chronic intermittent hypoxia (CIH)-induced endothelial dysfunction (Chen et al., 2017b). This evidence concerns the gene EDN1 and endothelial dysfunction.