Surface potentials and the control of amphibian limb regeneration

The relationship between surface potentials and amphibian limb regeneration is examined. The wound surface becomes increasingly positive for several days after amputation but then decreases again, often becoming negative for a variable period during blastemal growth. The same changes of surface potentials are observed during wound healing alone, in the absence of amputation and following amputation of irradiated or denervated limbs. Similar changes occur in non-regnerating frog arms. These observations and other cited reasons lead to the conclusion that surface potentials do not control regeneration.