Figure 3: Effect of KSO, NPFF, and KP peptides on forskolin prevention of H2O2 toxicity in ND-7/23 cells. Cells were exposed to H2O2 either alone or in the presence of forskolin with KSO, NPFF, or KP peptides for 2 hours prior determination of cell viability by MTT reduction. The effects of the NPFF receptor antagonist RF9 and the GPR-54 antagonist KP234 were also determined. Results are expressed as % Control MTT reduction (mean ± sem; ). * versus H2O2 alone; † versus H2O2 plus forskolin; one-way ANOVA.