Neutrophils [polymorphonuclear leukocytes (PMNs)] express several purinergic receptors, including the nucleotide receptors P2Y2 and P2X7 and the adenosine receptor subtypes A 1 , A 2A and A 3 . Activation of these receptors modulates PMN function and ultimately, in concert with other cells, affects the host's innate inflammatory response. PMN activities that can be altered by purinergic receptor stimulation include adhesion, aggregation, migration, phagocytosis, microbicidal function, release of tissue-damaging products and apoptosis. Interventions that alter PMN purinergic receptor stimulation are being developed to reduce organ dysfunction in conditions such as sepsis, ischemiaÁreperfusion injury and the acute respiratory distress syndrome.