In the present study, we showed that (i) bile acids strongly decrease the expression of AQPs in pancreatic ductal cells, (ii) chronic or acute inflammation of the pancreas is associated with decreased expression of AQP1, (iii) the absence of AQP1 reduces ductal fluid and HCO3- secretion, (iv) and induces a more severe pancreatitis in a cerulein-induced pancreatitis model. The gene discussed is AQP1; the disease is pancreatitis.