MATERIAL and METHODS: Twenty-four male Wistar albino rats were randomly divided into 3 equal groups (n=8): Control (C), injury (I), and stem cell and injury (SI). The sciatic nerve of the rats in the I and SI groups was subjected to clip compression for 5 minutes. Moreover, approximately 5x10⁵ bone marrow-derived mesenchymal stem cells were given via tail vein of the rats in the SI group immediately after clip compression. The nerve conduction velocities and amplitudes of the rats were measured 30 days later. Then, the sciatic nerves were removed, and myelin damage grading and axon counting were performed. The data were analyzed by One- Way ANOVA and Tukey"s post-hoc test. P values less than 0.05 were considered to be statistically significant.

RESULTS: While the proximal, distal and mean latency values were higher in the I and SI groups than in the control group, the same measurements were lower in the SI group than in the I group. While the nerve conduction velocity, the amplitude of compound muscle action potential and the number of axons were lower in the I and SI groups than in the control group, the same measurements were higher in the SI group than in the I group. Moreover, myelin damage was found to be lower in the SI group than in the I group.

CONCLUSION: Systemic application of bone marrow-derived mesenchymal stem cells in a compression model of peripheral nerve injury has a positive impact on both myelin sheath and axon survival. Keywords : Bone marrow, Healing, Injury, Peripheral nerve, Mesenchymal stem cell, Nerve conductive velocity, Rats