Distribution of Superoxide Dismutase Activity in the Epidermis: Measurement with Electron Spin Resonance Spin Trapping

Superoxide dismutase (SOD) activity in cow snout epidermis was determined by the method of electron spin resonance (ESR) using the 5, 5 dimethyl-1-pyrroline-N-oxide (DMPO) spin trapping agent. The procedure was found to be a reliable measurement as compared with the ordinary method using xanthine oxidase NBT. SOD activity was distributed through the whole epidermis. This activity was higher in the lower layer than in the upper and middle layers.