Changes

**δ cells produce somatostatin. Low numbers in all islets.

**δ cells produce somatostatin. Low numbers in all islets.

**F cells produce pancreatic polypeptide

**F cells produce pancreatic polypeptide

**Glucagon raises the blood glucose level.

*Glucagon raises the blood glucose level.

**Insulin decreses the blood glucose level.

*Insulin decreses the blood glucose level.

**Somatostatin acts in a paracrine fashion to inhibit both glucagon and insulin secretion.

*Somatostatin acts in a paracrine fashion to inhibit both glucagon and insulin secretion.

**Pancreatic polypeptide is thought to be a cholecystokinin antagonist, and thus inhibits secretion of pancreatic juice.

*Pancreatic polypeptide is thought to be a cholecystokinin antagonist, and thus inhibits secretion of pancreatic juice.

===Glucagon===

===Glucagon===