DesArg10[Hoe 140] is a potent B1 bradykinin antagonist

DesArg10[Hoe 140] and Des(D-Arg1, Arg10)[Hoe 140], desArg10-analogs of the potent and stable B2 bradykinin (BK) receptor antagonist Hoe 140 were found to be potent and stable antagonists of the B1 receptor in vitro and in vivo. They were, however, less selective than DesArg9[Leu8]BK, the metabolically unstable B1 prototype antagonist. Surprisingly, Hoe 140, which behaved as a pure B2 antagonist in several smooth muscle preparations, had a considerable inhibitory effect against the B1 agonist DesArg9-BK in bovine aortic endothelial cells. This finding for the first time suggests that B1 receptors are heterogenous.