G-protein coupled receptor 171 is a protein that in humans is encoded by the GPR171gene.[5][6] It has been recently deorphanised, with its endogenous agonist being a neuropeptide BigLEN which is a cleavage product of ProSAAS. GPR174 has been found to be involved in processes such as pain, anxiety, and appetite regulation, as well as immune system function, and GPR174 agonists may represent a potential target for novel analgesic drugs. Interestingly it seems to show sex-selective signalling, with effects seen in male mice often absent in female mice.[7][8][9][10][11][12][13][14][15][16]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Jacobs KA, Collins-Racie LA, Colbert M, Duckett M, Golden-Fleet M, Kelleher K, et al. (Dec 1997). "A genetic selection for isolating cDNAs encoding secreted proteins". Gene. 198 (1–2): 289–296. doi:10.1016/S0378-1119(97)00330-2. PMID9370294.
^Kou F, Li XY, Feng Z, Hua J, Wu X, Gao H, et al. (2025). "GPR171 restrains intestinal inflammation by suppressing FABP5-mediated Th17 cell differentiation and lipid metabolism". Gut. 74 (8): 1279–1292. doi:10.1136/gutjnl-2024-334010. PMID40074327.
^Raddatz MC, Newson CM, Stott M, Campbell C, Bobeck EN (2025). "GPR171 is necessary for normal physiological functions and mood-related behaviors in males, but not females". Behavioural Brain Research. 490 115618. doi:10.1016/j.bbr.2025.115618. PMID40318809.