Receptor for opioid growth factor (OGF), also known as Met-enkephalin. Seems to be involved in growth regulation. The OGF/OGFR complex is probably translocated to the nucleus. Colocalized with OGF in the perinuclear region. Highly expressed in 6-day old cerebellum and brain. Lower expressed in adult cerebellum. The protein is detected in germinal cells of the cerebellum, in neurons of the deep cerebellar nuclei and in the glia in the medullary layer. Belongs to the opioid growth factor receptor family.