Figure 2. Effect of phototreatment with Zn porphyrins on MTT reduction and respiration.

Cells were preincubated for 24 h with Zn porphyrins, washed, resuspended in PBS and illuminated for 30 minutes. A: MTT reduction by cells illuminated after preincubation with ortho methyl, butyl or hexyl Zn porphyrins. Concentrations of compounds causing 50% inhibition of MTT reduction (IC₅₀) compared to controls are presented; B: Oxygen consumption by cells preincubated with 5 µM Zn porphyrins and illuminated. Mean ± S.E. is presented (n = 4); * p<0.05 compared to control.