Figure 8.

The activation of Akt signaling and eNOS phosphorylation initiated by the Panx-1 channel blockade depends on NADPH oxidase-mediated O₂^·– production. (a, b) Representative Western blots and densitometric analysis of Akt (a), eNOS (b), Akt phosphorylation at serine 473 (P-Akt^S473, (a)), and eNOS phosphorylation at serine 1177 (P-eNOS^S1177, (b)) observed in basal conditions (control) and during the treatment with 1 mM probenecid (Pb) in the absence or presence of 10 μM TEMPOL. The effect of TEMPOL alone is also shown. In the densitometric analysis, the changes in eNOS and Akt phosphorylation are expressed as the ratio of phosphorylated protein over total protein. (c) Time course of the vasodilation induced by 100 nM ACh in control conditions and in the presence of 1 mM probenecid alone or in combination with 10 μM TEMPOL or 100 μM apocynin. Arterial mesenteric beds were constricted with 70 mM KCl. The horizontal bar indicates the period of stimulation. (d) Maximum ACh-induced vasodilation attained during the application of probenecid or its vehicle in control conditions and in the presence of TEMPOL or apocynin. Numbers inside the bars indicate the n value. Values are means ± SEM. ^∗P < 0.05 vs. the control by one-way ANOVA plus the Newman-Keuls post hoc test. ^†P < 0.05 vs the vehicle by paired Student's t-test.