Electrophysiologic test in measuring the protective effect after target muscle injection of mesenchymal stem cells in injured sciatic nerve of rat

Objective To examine the effect of target muscle injection with mesenchymal stem cells in sciatic nerve injury of adult rat. Methods Human mesenchymal stem cells were isolated and cultured in vitro. Thirty-six rats were divided into normal saline group (NS group), muscle injection group at random. The sciatic nerve was crashed for 5 min. MSCs (100,000)were injected into muscle after 3 days of injury. Sciatic nerve function index (SFI), motor nerve conduction velocity (MCV), muscle evoked action potential (MAP) and regeneration axon counting were detected in the 3 d, 7 d, 14 d, 21 d, 28 d, 60 d respectively. Results Denervation, regeneration of nerve, regeneration of denervated muscle partly were observed in 2 groups of rat. Spontaneous activity and action potential were recorded earlier in muscle injection group. Nerve conduction velocity was increased faster in muscle injection group compared to controls.(P0.05). From 21 d, there was a significant difference in muscle injection groups. In 60 days, there was no difference in conduction velocity between them(P0.05), but the differences of CMAP amplitude were significant(P0.05). Conclusions Target Muscle injection with MSC is well distributed in denervated muscle, they can provide protect effect in some degree in regeneration of muscle and nerve after sciatic nerve injury in rat.