Trypsinogen (EC 3.4.23.18/20/21/23/24/26) is the precursor form of the pancreatic enzyme trypsin or a zymogen. It is found in pancreatic juice, along with amylase, lipase, and chymotrypsinogen. It is activated by enteropeptidase, which is found in the intestinal mucosa, to form trypsin. Once activated, the trypsin can activate more trypsinogen into trypsin. Trypsin cleaves peptide bond on carboxyl side of basic amino acids. Serum trypsinogen is measured using a blood test. High levels are seen i… (More on Trypsinogen)