Somatostatin
- 14–amino acid polypeptide secreted by δ (Delta) cells (5-10%, lie intermediate)
- Inhibits GI hormones
- Insulin
- Glucagon
- Pancreatic Polypeptide
- Gastric, pancreatic, and biliary secretions
- Controversy as to whether endogenous somatostatin influences the secretion of other islet hormones directly
- Synthetic octapeptides mimic the pharmacologic action of somatostatin
- Have a longer T1/2 than endogenous somatostatin
- More potent inhibitors of growth hormone, glucagon, and insulin secretion
- Used to treat exocrine and endocrine disorders of the pancreas, including secretory diarrhoea, bowel fistulas, pancreatic fistulas, and endocrine hypersecretory syndromes