Fig. 9.

a Observations made near a wound in rat cornea. (A) Neuron outgrowths are strongly aligned by the endogenous electric field and exhibit a more random orientation when the field is reduced by ouabain addition. (B) The rate of corneal wound healing is reduced in the presence of ouabain. (C) The frequency and orientation of division planes is influenced by the field strength. Aminophylline increases the transcorneal potential and stimulates an increase in the rate of cell division and orientation of the axis of division perpendicular to the field [57]. b Diagram of the setup for current supply to the wounds. The newt was placed in a three-compartment chamber with only the feet immersed in pools of pond water. This minimized shunting of the supplied current (left). The benzocaine-soaked pads for keeping the head and trunk moist and the animal anesthetized are omitted for the sake of clarity (right). A view of one current-supplying electrode and the two microelectrodes used for potential measurements [57]. c The diagram illustrates the interaction between electric fields. The electric field can be directly attached to the endogenous electric field of the wound, where applying EF (brown arrow) in the default direction of wound healing will enhance wound-induced endogenous EF (red arrow), thus increasing the wound healing rate. In contrast, reversing the direction of EF (blue arrow) against the default wound healing direction will suppress the endogenous EF in the wound (red arrow), thus reducing or even stop the normal wound healing behaviors [10]. d Directional angiogenesis is a vascular-like structure of a rat placed in a 3D armature chamber with the aortic ring growing toward the anode. On the left is the aortic ring after embedding; on the right is day 3, after 200 mV/mm EF treatment. Rod is 500 μm [10]