Figure 2

(A) MRP4 inhibition further increases secretin-induced zymogen activation. Intrapancreatic trypsin was fluorometrically assessed in animals pretreated with probenecid followed by the infusion of secretin alone or with ANF. *p < 0.05 and ***p < 0.001 versus control; ^#p = 0.05 versus secretin. Number of experiments: 5. (B, C) Blockade of MRPs with MK571 mimics probenecid response in the presence of secretin. Isolated pancreatic acini were pretreated with probenecid or MK571 and further exposed to secretin. Intrapancreatic trypsin (B) and intracellular cAMP (C) were assayed as detailed in Materials and Methods. S, secretin.