FIGURE 2.

P2X_1/5 receptor-mediated Ca²⁺-signaling in cortical astrocytes. (a) Acutely isolated astrocytes were loaded with Fluo-4 via a patch pipette. Fluorescent images were recorded simultaneously with transmembrane currents evoked by application of 100 µM ATP or 10 µM α,β-methylene ATP. [Ca²⁺]_i-transients are represented as the ΔF/F₀ ratio averaged over the cell soma (green traces). Holding potential was −80 mV. (b) Synaptically induced ionotropic Ca²⁺ signals in protoplasmic cortical astrocytes in situ. Cortical layer II astrocytes were loaded with Fura-2 in situ via patch pipette. Fluorescent images were recorded simultaneously with glial currents evoked by neuronal afferent stimulation in the presence of CNQX (control) and after application of 10 nM of NF-449, selective antagonist of P2X receptors. [Ca²⁺]_i-transients (green traces) are expressed as F₃₄₀/F₃₈₀ ratio. (Reprinted with permission from Ref 32. Copyright 2010 Elsevier)