P2Y receptors in microglia:: An intracellular Ca2+ study

In this study we used intracellular Ca2+ recording with the aim to characterize the repertoire of P2Y receptors in rat microglial cells, and to distinguish the specificity of the effects of low/basal versus high doses of nucleotides. By a pharmacological approach we confirmed the expression of a complex array of P2Y receptors. Uracil nucleotides (UTP, UDP) elicited a more sustained and frequent Ca" capacitative plateau compared to adenine nucleotides (ATP, ADP). The plateau could be inhibited by the mitochondrial uncoupler FCCP, indicating a possible role played by mitochondria. Low doses of nucleotides elicited low frequency oscillatory Ca2+ changes. We conclude that, depending on the type and concentration of the agonist, P2Y receptor activation causes distinct patterns of Ca2+ changes which might differently affect microglial functions.