The kallikrein-kinin system in inflammation.

Abstract

The kallikrein kinin system is shown diagrammatically in Figure 1 and indicates the various pathways by which kinin (bradykinin or lysyl bradykinin) can be formed. The intrinsic coagulation-kinin system is depicted on the left, and the tissue kallikrein-kinin pathway on the right. An up-to-date exposition of the various reactions of the intrinsic-coagulation pathway has been published in a recent review. In brief, it is initiated by Hageman factor autoactivation 2,3 conversion of prekalli-krein to kallikrein 4,5 a positive feedback in which Hageman factor is rapidly cleaved8by kallikrein 6,7 and cleavage of high molecular weight (HMW)-kininogen8. The prekallikrein is complexed to HMW-kininogen in plasma via the HMW kininogen light chain 9,10 The tissue pathway, by contrast, is dependent upon local secretion of tissue kallikrein by cells followed by digestion of low molecular weight (LMW)-kininogen to release lysyl-bradykinin; the latter peptide is rapidly converted to bradykinin by a plasma aminopeptidase 11 The source of kininogen available to the tissue system is dependent either upon local accumulation of plasma or kininogen that is present in interstitial fluid.KeywordsAllergy Clin ImmunolKinin ActivityHereditary AngioedemaTissue KallikreinPlasma KallikreinThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.