Somatostatin

Somatostatin is available in two molecular forms -14 and 28 amino acid peptides. It acts as a humoral regula­tory agent and found in CNS, pancreas and cells lining the GI tract.

Somatostatin may also acts as a neurotransmitter in retina and spinal cord. It inhibits variety of metabolic and digestive functions.

Pancreatic somatostatin is the secretion from δ cells of the islets of Langerhans

Somatostatin inhibits α, β and F cells thereby the secretion of insulin, glucagon and pancreatic polypeptide are inhibited.

Gastric somatostatin inhibits the secretion of gastrin, secretin, CCK and pancreatic exocrine secretions, HCl and pepsin secretions, GI motility and gall bladder activity, thereby the absorp­tion of nutrients.

Somatostatin secretion is stimulated by increased level of glucose, amino acids, catecholamines, acetylcholine and glucagon.