Submission Date


Document Type

Paper- Restricted to Campus Access



Second Department


Faculty Mentor

Ellen Dawley


Presented during the 19th Annual Summer Fellows Symposium, July 21, 2017 at Ursinus College.

Project Description

Unlike mammals, there are some animals that are capable of regenerating their spinal cord and still retaining uninhibited function. Ambystoma mexicanum, also known as axolotls, is one such animal. Axolotls are capable of regenerating lost or damaged tail back to an undamaged state that is functionally identical to the undamaged tail. An axolotl’s spinal cord extends all the way to the tip of its tail, meaning that if the tail is severed, then the spinal cord must also be regenerated. This ability has been extensively researched due to its implications for treatment of people with spinal cord injuries. However, the majority of the research done on the regenerating spinal cord involves juvenile axolotls that are only 1 to 3 cm long. Thus the effects of aging on spinal cord regeneration has not been well documented. In this study I focused on the rate of regeneration of spinal cord cells in 5-8 cm long juveniles. To accomplish this I injected 14 axolotls with BrdU, which integrates itself into the nucleus of dividing cells, and visualized it using an antibody stain and a confocal microscope. The specimens each had two amputations performed on their regenerated tail. Due to the lack of available comparisons, I was unable to determine if the regeneration rate of the juveniles were in any way different from that of the larva used in other studies. I was, however, able to determine that undergoing two amputation had not significantly impacted the percentage of BrdU labeled cells in the spinal cord.