Activated Müller Cells Involved in ATP-Induced Upregulation of P2X₇ Receptor Expression and Retinal Ganglion Cell Death

Figure 2

ATP-induced changes in P2X₇R protein expression in rat retinas. ATP (10 μM, 2 μL) was intravitreally injected every 7 days, and retinal sections or whole retinal extracts were made at different times after the injection. (a) Immunofluorescence labeling showing the changes in P2X₇R protein expression in rat retinal vertical slices taken from NS-injected retina (Ctr) (a1) and ATP-injected retinas from 1 week (1 w) to 6 weeks (6 w) after the injection ((a2)–(a5)). Note that P2X₇R protein expression was mainly in the GCL and the INL. (b) (b1)–(b5) show corresponding DAPI images. (c) The merged images of (a1) and (b1) (c1), (a2) and (b2) (c2), (a3) and (b3) (d3), (a4) and (b4) (c4), and (a5) and (b5) (c5), respectively. Scale bar, 20 μm for all images. GCL, ganglion cell layer; IPL, inner plexiform layer; INL, inner nuclear layer; OPL, outer plexiform layer; ONL, outer nuclear layer. (d) Representative immunoblots showing the changes in P2X₇R protein expression in NS-injected retinas and ATP-injected retinas at different times after the injection. (e) Bar charts summarizing the average densitometric quantification of immunoreactive bands of P2X₇R proteins under different conditions. for each group. and versus Ctr.

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