【摘要】 目前临床应用的药物中约有40%是以G蛋白偶联受体（G protein-coupled receptors, GPRs）为作用靶点的，但至今仍有约90种GPRs为孤儿受体。GPR21主要存在于脑和脂肪组织中，其参与众多生理活动，如调节体质量、葡萄糖代谢、胰岛素敏感性和改善炎症等，具有成为治疗代谢性和炎症性疾病药物作用靶点的潜力。本文概要介绍GPR21的表达、结构、生理功能和信号通路等方面的研究进展，为后续进一步研究GPR21提供参考。更多还原

【Abstract】 At present, about 40% of the drugs in clinical application are targeted by G protein-coupled receptors(GPRs). However, there are about 90 GPRs which are still orphan receptors. GPR21 is an orphan GPR mainly expressed in brain and adipose tissue. It is involved in many physiological activities, such as regulating body weight, glucose metabolism, insulin sensitivity and reducing inflammation, so it has the potential to treat metabolic and inflammatory diseases. This review introduces the discovery, expression, structure, physiological function and signaling pathways of GPR21 so as to provide reference for further research on GPR21 in the future.更多还原