Abstract:In this work, the changes in electrical parameters of cell membrane of Xenopus Oocytes were determined using routine microelectrode electrophysiological technique after incubation of the cells in frog Ringer solution containing free radical producing System for 6 hours. It was observed that the resting membrane potential was raised, and the membrane resistance and time constant were decreased. The effects of free radical on the cells can be prevented and reversed by incubation with superoxide dismutase or Lycium barharum polysaccharide.