Effect of Some Analogues of Bradykinin Upon Vascular Permeability. ∗

Abstract

Summary

The decapeptide, lysyl brady-kinin (Kallidin I) was more effective in increasing vascular permeability in the skin of guinea pigs than was the nonapeptide, bradykinin, or Kallidin II. Bradykinin has been reported to be more active in some other assays measuring pharmacological effects than lysyl bradykinin. All other analogues of bradykinin tested were less active than bradykinin in the permeability assay with the exception of glycyl bradykinin, another decapeptide, which had an equal effect. While an inactive analogue of bradykinin did not block increased vascular permeability induced by a later injection of bradykinin, two active compounds, lysyl bradykinin and bradykinin inhibited the effect of a subsequent injection of either one into the same site.

Synthetic bradykinin BRS-640 was generously provided by Dr. Harry Baird, Sandoz Pharmaceuticals, Hanover, N. J. Dr. Ernest D. Nicolaides generously provided bradykinin analogues, which were synthesized in the Research Laboratories of Parke Davis & Co., Ann Arbor, Mich. Dr. Miklos Bodanszky Dept. of Chemistry, Western Reserve University, has provided helpful criticisms of this manuscript.