Fig. 4.

Ang II induction of premature senescence in hVSMC is dependent upon cellular oxidants, mtETC activity and mitochondrial superoxide. Quiescent cells were pre-incubated with catalase (A), NAC (B), SOD (C) or inhibitors of the mtETC, rotenone (D) or TTFA (E) or the mitochondrial ${\mathrm{O}}_2^{-}$ scavenger mitoTEMPO (F) for 4 h prior to induction of senescence with 1×10⁻⁸ mol/L Ang II. Following treatment, senescence was assessed by staining for SA-β-gal activity. Bars represent mean+SD; n=3–5. ^⁎⁎p<0.01, ^⁎⁎⁎p<0.001, ^⁎⁎⁎⁎p<0.0001 compared with control. ^†p<0.05, ^††p<0.01, ^†††p<0.001 compared with Ang II alone.