So what do we call GPR18 now?


SPH Alexander, School of Biomedical Sciences, University of Nottingham Medical School, Nottingham NG7 2UH, UK. E-mail:


The further characterization of the orphan GPCR GPR18 conducted by McHugh et al. in this issue of the British Journal of Pharmacology has generated a pharmacological profile that raises some interesting questions about the nomenclature of this receptor and may also prompt some questions about the pharmacological definition of the classical cannabinoid receptors, CB1 and CB2.

LINKED ARTICLES This article is a commentary on McHugh et al., pp. 2414–2424 of this issue and is part of a themed section on Cannabinoids in Biology and Medicine. To view McHugh et al. visit To view the other articles in this section visit To view Part I of Cannabinoids in Biology and Medicine visit