| Modification Notes |
The 387 amino acid protein galanin receptor-2 (GALR2) protein belongs to a family of G protein-coupled receptors that specifically bind galanin, a neuropeptide distributed throughout the central and peripheral nervous system, the pituitary gland, the gastrointestinal tract and in the endocrine and exocrine pancreas (1-3). GALR2 mRNA is abundant in parvocellular paraventricular nuclei, but in contrast to GALR1, is not expressed in magnocellular neurons or in supraoptic nuclei. Like GALR1 mRNA, GALR2 mRNA is expressed in the POMC neurons, dorsomedial nucleus, arcuate nucleus and in restricted peripheral tissue, with highest mRNA levels in human small intestine (2-5). Galanin-like peptide (GALP) is a putative endogenous ligand for GALR2 (2). Binding of GALP to GALR2 results in increased GTPgS binding to the membrane-bound GALR2 (6). GALR2 is therefore a receptor that mediates important functions of galanin in the hypothalamic-pituitary axis, plays a role in hippocampal and cerebellar function (7) and mediates jejunal contraction (8). |