Morphology of NIH3T3 cells after DNP treatment. NIH3T3 cells treated with different concentrations of DNP (0.025 mM – 2 mM) for 20 min were round and shrunken. After 48 h of reoxygenation, cells regained normal morphology except in case of 1 mM and 2 mM concentrations in which most of the cells died (Fig. 1A-B). Images were taken at 10X magnification under inverted phase contrast microscope.