G protein-coupled receptor 37 (GPR37), also known as the prosaposin receptor, is a class A GPCR predominantly expressed in the central nervous system, especially in oligodendrocytes and select neuronal populations. GPR37 has been identified as a receptor for prosaposin and prosaptide peptides, mediating neuroprotective and glioprotective signaling. In mice, Gpr37 plays important roles in oligodendrocyte differentiation, myelination, and cellular stress responses, as well as modulation of dopaminergic signaling pathways. Functionally, GPR37 is involved in cell survival, ER stress regulation, and protein quality control, and has been linked to Parkinson's disease-related mechanisms, including its interaction with parkin (PARK2) and propensity to form intracellular aggregates under pathological conditions.