ABSTRACT

It has been over seven decades since Drury and Szent-Gyorgyi first proposed the concept of purinergic signalling. It is now widely accepted that adenosine 5’-triphosphate (ATP) can act as a neurotransmitter in both the peripheral and central nervous systems. Extracellular ATP exerts its biological effects by acting at cell surface receptors consisting of two distinct types of P2-purinoceptors, namely P2X and P2Y receptors. P2X receptors are ligand-gated ion channels that mediate fast cell-to-cell signalling, while the P2Y receptors are G-protein coupled receptors associated with slower signal transduction mechanisms. In recent years, significant advances have been made with regard to the functional significance of these receptors in many regions of the central nervous system. In particular, there is now a growing body of evidence to suggest a diverse role for purinergic signalling within numerous regions of the brain stem. Hence, this review will begin with a brief historical overview of ATP neurotransmission, followed by a more detailed account of the specific roles of P2-purinoceptors in various brain stem structures. The review will conclude by highlighting some of the obstacles currently facing purinergic research. It is envisaged that this review will provide a timely update of our current understanding of purinergic signalling within the hind brain.