Effects of Age on the Morphology of Regenerated Spinal Cords in Axolotls

The healing process in humans and other mammals results in the formation of scar tissue as well as failure to regenerate nerves. In the case of a spinal cord injury (SCI), because the nerves do not regenerate, there is often loss of function to some degree or total loss of function in the worst cases. Many amphibians, such as the neotenic axolotl, in contrast do not heal in this way and rather have the remarkable ability to perfectly regenerate limbs, tail, spinal cord, and other structures without the formation of scar tissue. Because of the many potential medical applications that the understanding of this process holds, much experimentation has been carried out to determine the mechanisms involved in the regeneration process. Previous research in Dr. Ellen Dawley’s lab has showed that older axolotls have the potential to incorrectly regenerate the spinal cord, resulting in abnormal regrowths. In order to investigate this phenomenon further, this study focuses on whether age has an influence on the regeneration process. To accomplish this, I prepared cross-sections of both the original tail and the 1 week old regrowth of axolotls of various ages (ranging from 3 months to over 5 years of age), and used the H&E staining technique to better visualize the spinal cord. Light microscopy was then used to view and compare the morphology of the pre- and post-amputation spinal cords