Tocris Scientific Review Series Tocri-lu-2945 P2X and P2Y Receptors Kenneth A. Jacobson Subtypes and Structures of P2 Receptor Molecular Recognition Section, Laboratory of Bioorganic Families Chemistry, National Institute of Diabetes and Digestive and The P2 receptors for extracellular nucleotides are widely Kidney Diseases, National Institutes of Health, Bethesda, distributed in the body and participate in regulation of nearly Maryland 20892, USA. E-mail:
[email protected] every physiological process.1,2 Of particular interest are nucleotide Kenneth Jacobson serves as Chief of the Laboratory of Bioorganic receptors in the immune, inflammatory, cardiovascular, muscular, Chemistry and the Molecular Recognition Section at the National and central and peripheral nervous systems. The ubiquitous Institute of Diabetes and Digestive and Kidney Diseases, National signaling properties of extracellular nucleotides acting at two Institutes of Health in Bethesda, Maryland, USA. Dr. Jacobson is distinct families of P2 receptors – fast P2X ion channels and P2Y a medicinal chemist with interests in the structure and receptors (G-protein-coupled receptors) – are now well pharmacology of G-protein-coupled receptors, in particular recognized. These extracellular nucleotides are produced in receptors for adenosine and for purine and pyrimidine response to tissue stress and cell damage and in the processes nucleotides. of neurotransmitter release and channel formation. Their concentrations can vary dramatically depending on circumstances. Thus, the state of activation of these receptors can be highly dependent on the stress conditions or disease states affecting a given organ. The P2 receptors respond to various extracellular mono- and dinucleotides (Table 1). The P2X receptors are more structurally restrictive than P2Y receptors in agonist selectivity.