Protective effect of glial cell line derived neurotrophic factor on spinal motoneurons after sciatic nerve injury in rats

Objective To investigate the effect of glial cell line derived neurotrophic factor(GDNF) on spinal motoneurons following sciatic nerve axotomy. Methods Rats with the right sciatic nerve transected were used as models. Twenty four rats were randomized into a treated group (GDNF was injected into the silica-gel tube) and a control group (Isotonic saline was injected). After silicone tubulization of sciatic nerve in adult rats, normal saline was injected into silicone chamber of the control group, and GDNF solution was injected in the treated group during operation. Two weeks after operation, hindlimb motor functions were measured and spinal sections were stained by Nissl, acid phosphatase(ACP) enzyme histochemistry and TUNEL methods. Results Compared with the control group, the hindlimb motor function was improved, the percentage of the survived spinal motoneuron was increased from 85.3% to 95.8%( P 0.01), the percentage of AC P stained area was significantly decreased from 376% to 252%( P 0.01)and TUNEL positive cells were reduced from 34.8 to 13.2 ( P 0.01)in the treated group. Conclusions GDNF could protect the degenerated spinal motoneuron after sciatic nerve axotomy.