Norepinephrine may crosstalk with 5-HT to superimpose SAM on idiopathic pulmonary hypertension and PPHN, with histamine to create and add eosinophils to SCAD and with endothelin-1 to generate a field effect that forms a venous angiopathy terminating as venous FMD. This evidence concerns the gene EDN1 and pulmonary arterial hypertension.