Fig. 4.

S-nitrosylation of PTEN promotes eNOS phosphorylation by means of Akt activation. (A) Human endothelial F2 cells were exposed to 10 μM SNOC for the indicated periods of time. peNOS (at Ser-1177; Upper) and total eNOS (Lower) were detected by Western analysis. (B) Ratio of increased peNOS levels. Intensity level was quantified from blots by using NIH Image software. Values are means ± SEM, n = 3; *P < 0.01 by ANOVA. (C) Akt inhibitors block phosphorylation of eNOS stimulated by exposure to SNOC. Cultures were treated with 10 μM Akt inhibitor II or IV (or control) for 30 min and then incubated with 10 μM SNOC or control solution. The levels of peNOS and eNOS were examined 30 min later by Western analysis. (D) eNOS activity in protein homogenates was measured with a citrulline assay. Values are means ± SEM, n = 5; *P < 0.01 by ANOVA.