G-protein coupled receptor 171 is a protein that in humans is encoded by the GPR171 gene. 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. It seems to show sex-selective signalling, with effects seen in male mice often absent in female mice.