Peptide antagonist of the B2 bradykinin receptor (pKi = 10.3); conformationally constrained cyclized analog of HOE 140 (Cat. No. 3014). Blocks hypotension and bronchoconstriction in vivo. Displays selectivity for B2 over 29 other receptors and ion channels (pIC50 < 5.5). MW (observed): 1299.56.