Tian J H, Han J S
Neuroscience Research Institute, Beijing Medical University, Beijing, China.
Peptides. 2000 Jul;21(7):1047-50. doi: 10.1016/s0196-9781(00)00242-4.
Orphanin FQ/nociceptin (OFQ) is a recently discovered endogenous ligand for the novel opioid receptor-like receptor (ORL-1). There are numerous reports in the literature demonstrating paradoxical effects of exogenous OFQ on pain modulation. For example, OFQ produces a pronociceptive effect in the brain and an analgesic effect in the spinal cord. In order to better understand the physiological actions of OFQ, the present study focused on the pain-modulatory effect of endogenously released OFQ measured using antibody microinjection techniques. We found that electroacupuncture analgesia (EA) was increased by intracerebroventricular (i.c.v.) injection of an OFQ-antibody and decreased following intrathecal injection. Furthermore, i.c.v. OFQ-antibody partially reversed tolerance to both chronic morphine and chronic EA. These data suggest that endogenously released OFQ plays an important role in pain modulation, where pain sensitivity in the brain and spinal cord is increased and decreased, respectively.
孤啡肽/痛敏肽（OFQ）是最近发现的新型阿片样受体（ORL-1）的内源性配体。文献中有大量报道表明外源性OFQ对疼痛调节具有矛盾的作用。例如，OFQ在大脑中产生促痛作用，而在脊髓中产生镇痛作用。为了更好地理解OFQ的生理作用，本研究聚焦于使用抗体微量注射技术测量内源性释放的OFQ的疼痛调节作用。我们发现，脑室内注射OFQ抗体可增强电针镇痛（EA），而鞘内注射则降低电针镇痛效果。此外，脑室内注射OFQ抗体可部分逆转对慢性吗啡和慢性电针的耐受性。这些数据表明，内源性释放的OFQ在疼痛调节中起重要作用，其中大脑和脊髓中的疼痛敏感性分别增加和降低。
