Abstract: There are provided PACAP which is a substance capable of inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells, a method for inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells in a human by PACAP administration, a pharmaceutical composition containing PACAP and, optionally, an anti-diabetic agent, and a method for evaluating a substance capable of inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells relying on the expression of Reg III? to be stimulated by PACAP as an index.

Abstract: There are provided PACAP which is a substance capable of inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells, a method for inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells in a human by PACAP administration, a pharmaceutical composition containing PACAP and, optionally, an anti-diabetic agent, and a method for evaluating a substance capable of inhibiting the hyperplasia of pancreatic cells and/or the hypersecretion of insulin by pancreatic cells relying on the expression of Reg III? to be stimulated by PACAP as an index.