Model of inherited pancreatitis. In the normal pancreas (left) trypsin that is prematurely activated within the pancreas is inhibited by SPINK1 and in the second line by trypsin and mesotrypsin preventing autodigestion. In inherited pancreatitis (right) mutations in PRSS1 or SPINK1 lead to an imbalance of proteases and their inhibitors resulting in autodigestion. The role of CFTR is until now poorly understood. Abbreviations: AP = activation peptide (According to Witt, ).