of pro-inflammatory biomarker of the same individual may help identify the causes of inflammation and potentially assist developing an efficient translational application of relevant therapeutic interventions. Purinergic receptors present promising potential for PET imaging of the neurological disorder biomarkers. These receptors have experienced an exciting journey since the discovery of their first member in early 20th century. Currently, a number of 11C and 18F PET radioligands of the adenosine, particularly the A1 and A2A receptors, and the fast synaptic P2X receptor subtypes, in particular, the P2X7 receptor have helped to elucidate the expression and functions of these purinergic receptors in CNS disorders. Despite emerging facts regarding participation of the P2Y signaling in the brain, their functions are not fully recognized. This is largely due to lack of availability of selective nonnucleotide and brain penetrable ligands to be radiolabeled as PET radiotracer for evaluation of their expression and functions in the brain. However, a list of P2Y receptor ligands have been mentioned in this review to enlighten and guide interested scientists in discovering novel PET ligand for noninvasive approach to evaluate the P2Y receptor contribution in the brain disorders and especially the neurodegeneration diseases.
