Phorbol ester induces intracellular translocation of phospholipid/Ca2+-dependent protein kinase and stimulates amylase secretion in isolated pancreatic acini.

Treatment of intact rat pancreatic acini with phorbol ester (12-O-tetradecanoyl-phorbol-13-acetate, TPA) resulted in a time- and concentration-dependent translocation of phospholipid/Ca2+-dependent protein kinase (PL/Ca-PK) from the soluble fraction. Redistribution of PL/Ca-PK was concurrent with stimulation of amylase secretion by TPA-treated acini. Polymyxin B, a potent and selective inhibitor of PL/Ca-PK completely inhibited TPA-induced amylase secretion. These findings are consistent with a role for PL/Ca-PK in the regulation of pancreatic exocrine secretion.