Galanin receptors in GtoPdb v.2021.3

Galanin receptors (provisional nomenclature as recommended by NC-IUPHAR [57]) are activated the endogenous peptides galanin and galanin-like peptide. Human is a 30 amino-acid non-amidated peptide [52]; in other species, it 29 amino acids long C-terminally amidated. Amino 1-14 of highly conserved mammals, birds, reptiles, amphibia fish. Shorter species (e.g. human galanin-1-19 [21] porcine galanin-5-29 [170]) N-terminally extended forms seven nine residue elongated [22, 170]) have been reported. More recently, newly-identified peptide, spexin (SPX), has reported to activate GAL2 GAL3 (but not GAL1) heterologous expression systems; alter GAL2/3 receptor-related behaviours animals [89].