Kallikreins are a class of serine proteases that affect the release of vasodepressor peptides or kinins from a plasma substrate. PPACKII is a specific and irreversible inhibitor of glandular and plasma kallikreins. At micromolar concentrations it has been shown to prevent apolipoprotein proteolysis in dextran sulfate-precipitated human plasma LDL and to inhibit serum atrial natriuretic peptide cleavage. PPACKII has also been reported to inactivate the amidolytic activity of native human Hageman Factor (Factor XII) at 5.3 μM.
