A high-dose of caerulein, the isozymes of cholecystokinin (CKK) and the regulator of pancreatic secretion, have been demonstrated to inhibit the formation of dense mature vacuoles in acinar cells.33 However, the disruption of vacuoles can lead to abnormalities in the levels of digestive enzymes and lysosomal hydrolases, which are essential in the activation of intracellular cathepsin B and trypsin.34 Importantly, cathepsin B and trypsin are the main causes of the self-digestion of the pancreas.34 In this case, we applied caerulein as the inducer to build the rat model of acute pancreatitis. Here, CTSB is linked to acute pancreatitis.