Rat-strain differences in recovery following peripheral-nerve allotransplantation.

The rat model is commonly utilized in peripheral nerve research. Due to the short length of the rat limb and the animal's inherent neuroregenerative capacity, the timing of assessment of nerve regeneration is critical, and significant differences between groups can be lost if assessment is done too late. Additionally, the comparison of data from different rat-strain combinations has been questioned. This study better defines the time course of recovery after peripheral nerve grafting, and examines differences between Buffalo (BUF), Lewis (LEW), and ACI rats. Tibial-nerve isografts and allografts were performed and harvested at 6, 8, 10, or 14 weeks. Histomorphometry documented a statistically significant difference in the ACI/LEW and LEW/LEW combination at 10 weeks. No strain differences in graft rejection were noted. The optimal time to assess for histomorphometric differences in the ACI/LEW and LEW/LEW combination is at 10 weeks postoperatively.