Transected dorsal column axons within the guinea pig spinal cord regenerate in the presence of an applied electric field

Abstract

Using an implanted battery and electrodes, we have imposed a weak, steady electrical field across partially severed guinea pig spinal cords. We have analyzed regeneration of dorsal column axons in experimental animals and sham-treated controls at 50-60 days postinjury by anterograde filling of these axons with the intracellular marker horseradish peroxidase and by employing a marking device to identify precisely the original plane of transection (J. Comp. Neurol. 250: 157-167, '86). In response to electric field applications, axons grew into the glial scar, as far as the plane of transection in most experimental animals. In a few animals axons could be traced around the margins of the lesion (but never through it). Moreover, these fibers returned to their approximate positions within the rostral spinal cord before turning toward the brain. In sham-treated controls, ascending axons were found to terminate caudal to the glial scar, and rarely were any fibers found within the scar itself. Axons were never observed to cross into the rostral cord segment. These findings suggest that an imposed electrical field promotes growth of axons within the partially severed mammalian spinal cord, that a steady voltage gradient may be an environmental component necessary for axonal development and regeneration, and that some component(s) of the scar impede or deflect axonal growth and projection.

H+ pump-dependent changes in membrane voltage are an early mechanism necessary and sufficient to induceXenopustail regeneration

“…Imposition of currents on the order of 10 A across severed spinal cords results in remarkable augmentation of regeneration in lamprey and guinea pig (Borgens et al, 1987;Borgens et al, 1990;Borgens et al, 1986). Applied electric fields are known to enhance limb regeneration in amphibia (Borgens et al, 1979;Borgens et al, 1977), and sciatic (Kerns and Lucchinetti, 1992;McDevitt et al, 1987) and optic nerve repair in mammals.…”

Role of electrical stimulation for rehabilitation and regeneration after spinal cord injury: an overview

“…Proliferation and faster growth rate was seen towards the cathode (negative pole). In experiments where the cathode electrode was placed rostral to the injury functionally only sensory recovery (ascending fibres) was established [9,11]. In other experiments, Borgens et al created specific lesions in the spinal cords of guinea pigs, which permanently eliminated a specific spinal reflex in the dorsal column.…”

Electrotaxis of lung cancer cells in ordered three-dimensional scaffolds

“…2,3 Such migration is also suggested to be related to the directional growth of cells and tissues during development and regeneration. [4][5][6] To illustrate the underlying mechanism, many in vitro experiments have been performed to study the electrotaxis of various cell types in response to dcEFs with a magnitude of a few tens to hundreds of mV/mm, similar to that experienced in vivo (e.g., at human skin wounds). Many cells include lymphocytes, 7,8 cancer cells, 9,10 leukemia cells, 3 and stem cells 11 were demonstrated to show evident electrotaxis effect.…”