activated kininogen:C1q binding protein tetramer Plasma kallikrein kallikrein:kininogen:C1q binding protein tetramer kallikrein:kininogen:C1q binding protein tetramer -> kallikrein + activated kininogen:C1q binding protein tetramer + bradykinin Authored: D'Eustachio, P, 2005-01-20 14:44:36 EC Number: 3.4.21 Edited: D'Eustachio, P, 0000-00-00 00:00:00 Pubmed3484703 Pubmed4054110 Pubmed500690 Pubmed9427705 Reactome Database ID Release 43158311 Reactome, http://www.reactome.org ReactomeREACT_2004 The cleavage of kininogen (HK, high molecular weight kininogen) yields activated kininogen and the vasoactive peptide bradykinin (Kerbirou and Griffin 1979; Lottspeich et al. 1985; Kellerman et al. 1986). In vivo, this reaction is catalyzed by activated kallikrein, takes places within the kallikrein:kininogen:C1q binding protein tetramer complex on the endothelial cell surface, and results in the release of kallikrein and bradykinin (Motta et al. 1998). The hormonal functions of bradykinin will be annotated in a future version of Reactome.