CPN1 and angioedema: Other kinin product of the KKS is DABK, a stable and active BK metabolite originated by proteolytic action of carboxypeptidase M (CPM) and carboxypeptidase N (CPN), also known as kininase I. Increased DABK levels are responsible for increasing vascular permeability, thus promoting angioedema, and pro-inflammatory repercussions, which may be blocked by the action of ACE2, as this enzyme is able to degrade it [23].