ATP and pain

Abstract

Many decades have passed since the pain-producing properties of ATP were demonstrated in both animals and humans. However, the more recent discovery of a family of ion channels for which ATP is a ligand and which are expressed by nociceptive neurons, has led to a resurgence of interest into the physiological and pathophysiological actions of ATP. This article considers the extent to which available evidence supports the notion that ATP receptors might be important novel analgesic targets. The hypothesis that ATP is a pain mediator is considered in terms of: the distribution of ATP receptors (specifically the P2X ion channel family); whether ATP release occurs under appropriate conditions; the evidence that ATP is capable of initiating pain in humans and pain-related behaviour in animals; and, lastly, the analgesic effects of pharmacological or molecular block of ATP receptors.