Galanin is an important neuromodulator present in the brain, gastrointestinal system, and hypothalamopituitary axis. It is a 30-amino acid non-C-terminally amidated peptide that potently stimulates growth hormone secretion, inhibits cardiac vagal slowing of heart rate, abolishes sinus arrhythmia, and inhibits postprandial gastrointestinal motility. The actions of galanin are mediated through interaction with specific membrane receptors that are members of the 7-transmembrane family of G protein-coupled receptors. GALR2 interacts with the N-terminal residues of the galanin peptide. The primary signaling mechanism for GALR2 is through the phospholipase C/protein kinase C pathway (via Gq), in contrast to GALR1, which communicates its intracellular signal by inhibition of adenylyl cyclase through Gi. However, it has been demonstrated that GALR2 couples efficiently to both the Gq and Gi proteins to simultaneously activate 2 independent signal transduction pathways.
Bloomquist BT, Beauchamp MR, Zhelnin L et al. (1998). "Cloning and expression of the human galanin receptor GalR2.". Biochem. Biophys. Res. Commun.243 (2): 474–9. doi:10.1006/bbrc.1998.8133. PMID9480833.CS1 maint: Explicit use of et al. (link)
Fathi Z, Battaglino PM, Iben LG et al. (1998). "Molecular characterization, pharmacological properties and chromosomal localization of the human GALR2 galanin receptor.". Brain Res. Mol. Brain Res.58 (1-2): 156–69. doi:10.1016/S0169-328X(98)00116-8. PMID9685625.CS1 maint: Explicit use of et al. (link)
Kolakowski LF, O'Neill GP, Howard AD et al. (1998). "Molecular characterization and expression of cloned human galanin receptors GALR2 and GALR3.". J. Neurochem.71 (6): 2239–51. doi:10.1046/j.1471-4159.1998.71062239.x. PMID9832121.CS1 maint: Explicit use of et al. (link)
Berger A, Tuechler C, Almer D et al. (2002). "Elevated expression of galanin receptors in childhood neuroblastic tumors.". Neuroendocrinology75 (2): 130–8. doi:10.1159/000048229. PMID11867941.CS1 maint: Explicit use of et al. (link)
Berger A, Lang R, Moritz K et al. (2004). "Galanin receptor subtype GalR2 mediates apoptosis in SH-SY5Y neuroblastoma cells.". Endocrinology145 (2): 500–7. doi:10.1210/en.2003-0649. PMID14592962.CS1 maint: Explicit use of et al. (link)