“Background: The endocannabinoid system is a neuromodulatory system implicated in cellular processes during both development and regeneration. The Mexican axolotl, one of only a few vertebrates capable of central nervous system regeneration, was used to examine the role of the endocannabinoid system in the regeneration of the tail and spinal cord following amputation.
Results: The endocannabinoid receptor CB1 was upregulated in the regenerating axolotl spinal cord by 4 hours following tail amputation, and this upregulation persisted for at least 14 days. The endocannabinoid receptor CB2 was upregulated later, between 7 and 14 days after tail amputation. Both CB1 and CB2 were located in ependymoglia and neurons within the regenerating spinal cord. Treatment with inverse agonists to inhibit CB1 (AM251) or CB2 (AM630) inhibited spinal cord and tail regeneration. During the first 7 days after injury, CB1 and CB2 expression was also necessary for the proliferation of ependymoglial cells and the regeneration of axons into the newly regenerated tail tissue. However, only CB1 was necessary for the differentiation of ependymoglia into immature neurons.
Conclusions: These studies are the first to examine the role of the endocannabinoid system during spinal cord regeneration in a regeneration-competent vertebrate.”
https://pubmed.ncbi.nlm.nih.gov/40377265/
“In summary, we provide evidence that CB1 and CB2 receptors are present in both ependymoglia and neurons of the regenerating axolotl spinal cord, and may play an essential role in creating a permissive environment for spinal cord regeneration in this vertebrate species. More specifically, the endocannabinoid receptors may regulate the proliferation and differentiation of ependymoglial cells into immature neurons, prevent glial scar formation, and promote regenerating axon elongation. In the future, it will be important to examine the role of the endocannabinoid system in interactions between neurons and the ependymoglia and in conjunction with other important signaling pathways important for the ependymoglial responses to trauma, and/or their regulation of microglia in the regenerating axolotl spinal cord.”
https://anatomypubs.onlinelibrary.wiley.com/doi/10.1002/dvdy.70035