Characterization of urinary metabolites from four synthetic bradykinin potentiating peptides (BPPs) in mice

BPPs have been identified in the venom of the Bothrops jararaca snake, or deduced from precursor proteins expressed either in the venom gland or in the brain of the snake. Their potentiating activity on bradykinin (Bk) is assumed to occur through a somatic angiotensin-converting enzyme (sACE) inhibitory mechanism. We have demonstrated that synthetic BPPs show remarkable functional differences, despite their high amino acid sequence similarities. Recently, we demonstrated that BPP-10c, after i.p. administration, was found in its intact form and in the form of a unique metabolite (des-Pro10 BPP-10c) in mouse urine. Given this finding, we selected a number of BPPs with different structure-activities – BPP-5a (