somatostatin receptor type 2, member of the class A family of seven-transmembrane G protein-coupled receptors
G protein-coupled somatostatin receptors (SSTRs), which display strong sequence similarity with opioid receptors, binds somatostatin, a polypeptide hormone that regulates a wide variety of physiological such as neurotransmission, endocrine secretion, cell proliferation, and smooth muscle contractility. SSTRs are composed of five distinct subtypes (SSTR1-5) which are encoded by separate genes on different chromosomes. SSTR2 plays critical roles in growth hormone secretion, glucagon secretion, and immune responses. SSTR2 is expressed in the normal human pituitary and in nearly all pituitary growth hormone adenomas.
Comment:based on the structures of some class A family members with bound ligands (peptides or chemicals), agonists, or antagonists
Comment:Small-molecule chemical ligands tend to bind deeper within the receptor core, compared to a peptide ligand neurotensin, which binds towards the extracellular surface of its receptor.
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