Methionyl-lysyl-bradykinin

There are 3 known plasma kinins, namely the nonapeptide bradykinin or kallidin-9 [154, 157, 158, 363, 364, 473, 523], lysyl-bradykinin or kaUidin-10 [499,665] and methionyl-lysyl-bradykinin [155,159,556]. These pharmacologically active polypeptides behave simlarily, although quantitative differences exist between them [141, 156, 412]. Bradykinin increases vascular permeability in the rat after intradermal injection [82,107,167,633] and also after sub-plantar injection into the paw [110, 210, 389, 601], and as such plasma kinins are potential mediators of the anaphylactoid oedema. 

D.F.Elliott and G.P.Lewis, Methionyl-Lysyl-Bradykinin, a New Kinin from Ox Blood, Biochem. J. 95, 437-447 (1965). 

The name kinin in this text always refers to three distinct biologically active peptides nonapeptide bradykinin (nine amino acids), decapeptide kallidin (ten amino adds) and undecapepdde methionyl-lysyl-bradykinin (eleven amino adds). All other peptides will be characterized specifically. 

The chemical structures of bradykinin, kallidin and methionyl-lysyl-brady-kinin ( = methionyl-kallidin) are shown in Figure 6. 

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