“The GPR55 receptor is expressed abundantly in the brain, especially in the striatum, suggesting it might fulfill a role in motor function. Indeed, motor behavior is impaired in mice lacking GPR55, which also display dampened inflammatory responses. Abnormal-cannabidiol (Abn-CBD), a synthetic cannabidiol (CBD) isomer, is a GPR55 agonist that may serve as a therapeutic agent in the treatment of inflammatory diseases. In this study, we explored whether modulating GPR55 could also represent a therapeutic approach for the treatment of Parkinson’s disease (PD). These results demonstrate for the first time that activation of GPR55 might be beneficial in combating PD.” https://www.ncbi.nlm.nih.gov/pubmed/28807673 http://www.sciencedirect.com/science/article/pii/S0028390817303842

“The orphan receptor GPR55 is a novel cannabinoid receptor”  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2095107/