Figure 1

Effect of NO exposure on HO-1 mRNA induction and stabilization. A. NIH3T3 cells were treated as controls or with an acute exposure to 0.5 mM SPER/NO for 1 h. AD was added to block transcription and total RNA was extracted at the indicated times. HO-1 mRNA expression was monitored by northern blotting and normalized to GAPDH expression. The same blot was also probed for the expression of unstable CL100 mRNA.B. Quantification shows the fitted decay lines, calculated from three independent experiments. Data points show the mean and standard errors. * p < 0.05 as compared the HO-1 mRNA remaining (% of initial) in untreated controls at the corresponding times. C. NIH3T3 cells were treated with the indicated concentrations of DETA/NO for 6 h prior to the addition of AD, and the percentage of HO-1 mRNA remaining was quantified at the indicated time points.D. Quantification shows the fitted decay lines, calculated from two independent experiments. Data points show the mean and standard errors. E. In parallel experiments, cells were trypsinized immediately after the treatment or at 8 h and 24 h after treatment, followed by trypan blue staining. To estimate viability, the values were normalized to 100% at time 0 h in untreated controls. Quantification in panel E shows the mean and standard error of three independent experiments, except for 0.5 mM dose, which corresponds to one experiment. ** p < 0.01, * p < 0.05 as compared to untreated controls at the corresponding times.