EDN1 and pulmonary arterial hypertension: Norepinephrine can crosstalk with other pressor agents to create SAM lesions—serotonin with idiopathic pulmonary hypertension and persistent pulmonary hypertension in the newborn, histamine in spontaneous coronary artery dissections with eosinophilia, and endothelin-1 in a field effect generated by SAM that creates venous fibromuscular dysplasia.