EDN1 and systemic sclerosis: The SSc vascular damage is characterized by the presence of a characteristic processes with a vasomotor instability with an imbalance of vasoactive factors: overproduction of vasoconstrictors (ET-1) and underproduction of vasodilators (NO and prostacyclin) [6,7,8,9,10,11,12,13,22,23,24,25,106,107,108,109].