Angiotensin II is a peptide hormone known best as a vasoconstrictor with central roles in chronic hypertension, heart failure, and stroke. It is an octapeptide typically generated by the removal of two residues from angiotensin I by angiotensin-converting enzyme (ACE). Angiotensin II is a ligand for at least two distinct receptors, AT1 and AT2, each evoking distinct signaling pathways and physiological responses. The development of antagonists for specific angiotensin II receptor subtypes represents a valuable alternative to ACE inhibitors.
