Somatostatin Receptor Type 2/SSTR2 [A8]

Somatostatin is a peptide hormone that regulates the endocrine system and affects neurotransmission and cell proliferation via interaction with G-protein-coupled somatostatin receptors and inhibition of the release of numerous secondary hormones. This hormone has two active forms produced by alternative cleavage of a single preproprotein: somatostatin-14, composed of 14 amino acids and somatostatin-28, a prohormone composed of 28 residues. Somatostatin is secreted by D-cells of the islets of Langerhans in pancreas, endocrine cells of the gastrointestinal tract, bronchopulmonary system, thymus, and C cells of the thyroid. Somatostatin positive cells may also be present in medullary thyroid carcinomas, C cell hyperplasia, thymic tumors and pulmonary small cell carcinomas. An antibody to Somatostatin can be used to identify pancreatic islet cell hyperplasia as well as islet cell tumors, such as somatostatinomas.