Partial blastema formation after amputation in adult mice.

The amputation surface of toes of adult mice was treated by repeated skin removal and exposure to a saturated solution of NaCl. Histological examination of treated appendages revealed the presence of wound epithelium, numerous irregularly oriented subepithelial cells, many of which were mitotically active as indicated by [3H] thymidine uptake, and a remodeled viable bone adjacent to subepithelial cells. Thus, tissues at the amputation site of mammals can resemble comparable tissues of newt limb stumps at an early stage of regeneration. Complete blastema formation was not achieved, however.