Co-expression of functional P2X4 and P2X7 receptors at adult neural progenitor cells of the mouse subventricular zone

Abstract

Co-localization of P2X4 and P2X7 subunits has been demonstrated in a number of tissues. It appears that these subunits form functionally interacting homomeric P2X4 and P2X7 receptors rather than heteromeric P2X4/7 receptors. We have recently reported that adult neural progenitor cells (NPCs) of the mouse subventricular zone (SVZ) possess P2X7 receptors. Cultured proliferating NPCs responded to higher concentrations of the prototypic P2X7 agonist diben- zoyl-ATP (Bz-ATP) with inward current, strongly inhibited by the selective P2X7 antagonist A438079, and moderately depressed by the P2X1-3,4 antagonist TNP-ATP, or the selective P2X4 antagonist 5-BDBD. Now we show in addition that ivermectin, a selective allosteric modulator of P2X4 receptors, uniformly potentiated the effect of lower Bz-ATP con- centrations; this potentiation was abolished by 5-BDBD. In conclusion, astrocyte-like cultured SVZ NPCs are endowed with P2X4 and P2X7 receptors shaping the characteristics of these cells with respect to ATP-dependent signalling.