Somatostatin Receptor 3 (SSTR3)

The biological effects of somatostatin are probably mediated by a family of G protein-coupled receptors that are expressed in a tissue-specific manner. SSTR3 is a member of the superfamily of receptors having seven transmembrane segments and is expressed in highest levels in brain and pancreatic islets. SSTR3 is functionally coupled to adenylyl cyclase.SSTR3 is a protein of 418 amino acids, with 45% and 46% identity with human SSTR1 and SSTR2, respectively. Functional studies using cells transiently coexpressing the human dopamine D1 receptor (DRD1) and human SSTR3 showed that somatostatin was able to inhibit dopamine-stimulated cAMP formation in a dose-dependent manner, indicating that SSTR3, unlike SSTR1 and SSTR2, was functionally coupled to adenylyl cyclase.