*4.2.3 CTRC*

CTRC is a digestive protease synthesized and secreted by the pancreatic acinar cells as an inactive proenzyme (zymogen), which becomes activated in the duodenum. Physiologic functions include degradation of trypsin and trypsinogen, as an important defensive mechanism in chronic pancreatitis [32]. Besides, CTRC is not only a digestive enzyme but also plays a role in regulating the activity of other digestive enzymes such as stimulating autoactivation of human cationic trypsinogen [28]. Furthermore, CTRC is an essential co-activator of pro carboxypeptidase A1 (pro CPA1) and pro carboxypeptidase A2 (pro CPA2) [33].

### *Current Approaches in Chronic Pancreatitis DOI: http://dx.doi.org/10.5772/intechopen.98214*

Mutations in the *CTRC* gene have been shown to increase the risk of CP and they are 30% prevalent among patients with CP. The three main pathways explaining the increased risk of CP involve (i) impaired trypsinogen and/or trypsin degradation; (ii) impaired activation of A-type carboxypeptidases, and (iii) induction of ER stress due to defective secretion [32].
