Figure 7. Effects of intraocular pressure (IOP) elevation on the P2X₇ receptor messenger RNA (mRNA) content in the retina. A: Alterations in P2X₇ receptor mRNA content (relative values to the normal control) in the retina after IOP elevation (open circles) or the retina after the sham treatment (closed circles). B: Effects of oxidized adenosine triphosphate (OxATP) on P2X₇ receptor mRNA content in the retina 2 days after IOP elevation. Data are expressed as mean± standard error of the mean (SEM; n=4–5). The asterisks indicate significant differences from the sham control eyes (A) or from the eyes without OxATP treatment (B; Mann–Whitney U-test, *p<0.05).