Role of P2X4 receptors on fatigue-enhanced muscle pain

Abstract

The chronic musculoskeletal pain is a great public health problem. They affect 47% of population and, because they are associated with muscle fatigue, they induce a decrease in physical activity and the ability to perform the activities of daily living. Although the clinical relevance of chronic muscle pain associated with muscle fatigue, the molecular mechanisms involved with this process are poorly known. It has been described that fatiguing stimuli induces release and accumulation of metabolites, such as ATP, which may contribute to muscle pain by activation of P2X4 receptors. There are evidences of the involvement of P2X4 on chronic pain, also, it was demonstrated that moderate exercises induce increase expression of P2X4 receptors mRNA on chronic fatigue syndrome patients. Therefore, considering the evidences of the involvement of P2X4 receptors in chronic pain and in muscle fatigue, the aim of this study is to investigate the role of P2X4 receptors in the fatigue-enhanced muscle pain. (AU)