Experiment Study Of The Influence Of Pleiotrophin On Preferential Motor Reinnervation After Peripheral Nerve Lesion

Objective To establish the selective regeneration model after peripheral nerve injury and detect the mRNA expression of PTN in this model.Method Twelve 3-week-old SD rats were randomly divided into two groups (A and B, n=6 each), and the right side of L2―L5 dorsal root ganglia postganglionic fibers was cut off, and the right femoral nerve was transectioned and then sutured. At the 4th week after operation in group A, and 8th week after operation in group B, the retrograde tracers (FD and TD) were separately marked into motor neurons via sensory and motor branches from the femoral nerve for neuron counting. To detect the mRNA expression of PTN in injuried cutaneous nerve,injuried motor nerve,the proximal of injuried nerve and denervated muscle using RT-PCR.Result A head into the motor nerve, sensory nerve and long into the two kinds of nerve the number of motor neurons were 141±27,84±14,72±11; and B , respectively, 176±12,68±8.A expression of PTN-mRNA in injuried motor nerve,injuried cutaneous nerve,th proximal of injuried nerve,denervated muscle and the lumbar of spinal cord were respectively 0.1487±0.0034,0.1287±0.0800,0.0664±0.0072,0.01485±0.0042,0.2832±0.1071;and B respectively,0.2836±0.0366,0.0561±0.06964,0.0119±0.0067,0.4161±0.1409,1.1437±0.1574。Conclusion The model is an ideal experimental platform with good repeatability to study selective regeneration after peripheral nerve injury. The experiment clarifies that there is a certain tendency between the volume of PTN and motor nerve regeneration. Objective To observe the effect of PTN on preferential motor reinnervation after peripheral nerve injury.Method Twelve 3-week-old SD rats were randomly divided into two groups (A and B, n=6 each), were operated by procedure mentioned above.A and B were intervened with PTN and PTN-Ig,repectively,at the transected site of the femoral nerve.Then 8th week after operation in group B, the retrograde tracers (FD and TD) were separately marked into motor neurons via sensory and motor branches from the femoral nerve for neuron counting. To detect the mRNA expression of PTN in injuried cutaneous branch,injuried motor branch,the proximal of injuried nerve and denervated muscle using RT-PCR.Result A head into the motor nerve, sensory nerve and long into the two kinds of nerve the number of motor neurons were 301±6,32±5,18±4 and B , respectively,. 202±6 , 38±8 , 16±5.The mRNA expression of PTN in injuried motor nerve,injuried cutaneous nerve,the proximal of injuried nerve,denervated muscle were 0.0554±0.0008,0.5925±0.0507,0.0804±0.0004,0.1405±0.0350,0.3301±0.0263;andBrespectively0.1152±0.1269,0.06643±0.0585,0.0116±0.0003,0.0226±0.0235,0.3775±0.1405.Conclusion PMR were enhanced in group A and decreased in group B; the expression of PTN significantly increased in group A,but decreased in group B. PTN may be involved and an important role in PMR.