Spinelli Francesco, Mu Linjing, Ametamey Simon M
Department of Pharmacy-Pharmaceutical Sciences, University of Bari "A. Moro", Bari, Italy.
Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland.
J Labelled Comp Radiopharm. 2018 Mar;61(3):299-308. doi: 10.1002/jlcr.3579. Epub 2017 Dec 29.
The cannabinoid type 2 (CB2) receptor is an immunomodulatory receptor mainly expressed in peripheral cells and organs of the immune system. The expression level of CB2 in the central nervous system under physiological conditions is negligible, however under neuroinflammatory conditions an upregulation of CB2 protein or mRNA mainly colocalized with activated microglial cells has been reported. Consequently, CB2 agonists have been confirmed to play a role in neuroprotective and anti-inflammatory processes. A suitable positron emission tomography radioligand for imaging CB2 would provide an invaluable research tool to explore the role of CB2 receptor expression in inflammatory disorders. In this review, we provide a summary of so far published CB2 radioligands as well as their in vitro and in vivo binding characteristics.
2型大麻素（CB2）受体是一种免疫调节受体，主要表达于免疫系统的外周细胞和器官。在生理条件下，CB2在中枢神经系统中的表达水平可忽略不计，然而在神经炎症条件下，已报道CB2蛋白或mRNA的上调主要与活化的小胶质细胞共定位。因此，CB2激动剂已被证实可在神经保护和抗炎过程中发挥作用。一种适用于CB2成像的正电子发射断层扫描放射性配体将为探索CB2受体表达在炎症性疾病中的作用提供一种非常有价值的研究工具。在本综述中，我们总结了迄今为止已发表的CB2放射性配体及其体外和体内结合特性。
