RESUMO
Extracellular purine and pyrimidine nucleotides produce the biologic effects involved in activating P2 receptors.P2 receptors are divided P2X and P2Y receptor subtypes.There is molecular and functional evidence for widespread expression of P2X and P2Y receptor subtypes in osteoblasts,osteoclasts and cartilage cells of the skeletal system.Working through P2 receptors,ATP and other nucleotides released into the bone microenvironment regulate formation and activity of bone and cartilage,including development,growth,turnover and repair of biological functions.The release of nucleotides is increased under inflammatory conditions,and localized ATP release could stimulate formation and activation of osteoclasts.Abnormalities of bone remodelling can produce a variety of skeletal disorders.P2 receptors play an important role in the inflammatory disease of bone.