EDN1 and Hypertension: Many mechanisms have been suggested in the relationship of insulin resistance with hyperinsulinemia and the hypertension; it has been suggested that, among these, the activity of endothelin-1 (ET-1), angiotensin II, and thromboxane A2 (TxA2), which are the vasoconstrictor compounds of the sympathetic nervous system activation, increased [34–36].