8-OH-DPAT enhances the antioxidant response. A. ARPE-19 cells were treated simultaneously with 300 μM paraquat and 20 μM 8-OH-DPAT for 48 hrs. RNA was extracted, followed by first strand cDNA synthesis and qPCR with primers for mRNAs encoding the antioxidant effector molecules indicated. Assays were performed in triplicate. Transcript levels relative to beta actin were set to one in untreated cells, and the values indicated are relative to untreated cells (*p<0.05 relative to untreated cells) Error bars indicate the standard deviation. B. ARPE-19 cells grown in low serum medium for days indicated were treated with paraquat (400 μM), and or 8-OH-DPAT (20 μM) for the last 48 hr. Electrical resistance was measured using EVOM2 (World Precision Instruments). Resistance in no cell control well was subtracted from those with cells (*p<0.05 relative to media only) Error bars indicate the standard deviation. C. ARPE-19 cells grown in low serum medium for 5 weeks were treated with paraquat, 8-OH-DPAT, or a combination of the two for 48 hrs. RNA was extracted and first strand cDNA was synthesized, which was used to carry out qPCR with the primers for the genes indicated. Transcript levels relative to beta actin were set to one in untreated cells, and the values indicated are relative to untreated cells (*p<0.05 relative to untreated cells). Error bars indicate the standard deviation.