The actions of kinin antagonists on B1 and B2 receptor systems.

The newly discovered bradykinin antagonist [Thi5,8,D-Phe7]Bradykinin, supplied by J.-M. Stewart and three other compounds, [D-Phe7]BK, [Thi5,8,D-Phe7]Bradykinin and [Thi6,9,D-Phe8]Kallidin synthesized in our laboratory, were tested for their ability to antagonize bradykinin in four B2 receptor systems, the guinea-pig ileum, the rabbit jugular vein, the dog carotid artery and the dog urinary bladder as well as against desArg9-bradykinin in the rabbit aorta (a B1 receptor system).