Effects Of NT-3Combined With MP And VitC On Nerve Regeneration In Rats With SCI

[Objectives]An SCI model was established in rats by spinal cord hemisection to observe theeffects of NT-3combined with MP and VitC on nerve regeneration, to investigate theroles of NT-3in nerve fiber regeneration, neuron edema reduction and limb functionalrecovery and to provide the theoretical foundations and experimental evidences fortreatment of SCI using NT-3combined with MP and VitC in clinic.[Methods]1．Totally36female SD rats (body weight250-300g) were selected andrandomly divided to six groups, namely normal group (group A, n=6), SCI groupwithout intervention (group B, n=6), NT-3treatment group (group C, n=6), NT-3+MPtreatment group (group D, n=6), NT-3+VitC treatment group (group E, n=6) andNT-3+MP+VitC treatment group (group F, n=6).2. Hemisection was performed on T10spinal cord followed by subarachnoidcatheter placement. In the normal control group, the lamina was opened and removed.Dural incision and catheter were performed under the operating microscope. In bothcontrol and treatment group, absorbable gelatin sponge containing MP liquid (and soon) was placed on the incision of spinal cord. The same dose was administrated dailyand extubation was performed1week later.3. Basso, Beattie and Bresnahan (BBB) scoring was performed on1day beforeand1,3,7,14and28days after the surgery.4. The rats were sacrificed4weeks following the SCI. Spinal cord specimenswere collected for HE staining, Nissl staining and nestin immunohistochemistry.Morphological structure of spinal nerve, Nissl bodies and expression of nestin proteinwere observed under the optical microscope. Statistical analysis was performed usingSPSS16.0software. [Results]1.Basso, Beattieand and Bresnahan (BBB) scoring for locomotor function.After SCI, BBB scores of right hind limb decreased significantly and the scores were0. With extension of time after surgery, the movement function of right hind limbshowed varying degrees of recovery. Among the six groups, group F was the fastestrecovery group, and it has the highest recovery comprehensive score, while group Bhas the lowest comprehensive score29days after the surgery.2. Histopathology. After SCI, there were mild sparse, edema and hemorrhage ingroup F as shown in HE staining. When compared with group A, sparse and edemawere more obvious and the number of neuron decreased accompanied with neuronalcells necrosis in other groups (group B to E) as shown in HE staining. The averagedensity of Nissl bodies in group F was significantly higher than other groups (P <0.05), but there was no statistic significance when compared with group B (P﹥0.05).3. Immunohistochemical staining of nestin. Endogenous regeneration andrepair in rat spinal cord hemisection injury begin with injury. Nestin expressedpositively in the astrocytes of white matter in group F. In group F, the expression andduration of nestin increased significantly when compared with other groups; in groupC, D, E, expression of nestin increased slightly when compared with group B.[Conclusions]1. NT-3combined with MP+Vit-c promoted behavioral and neurologicalfunction recovery after SCI in rat.2. NT-3combined with MP+Vit-c up-regulated nestin expression and increasedthe number of nissl bodies.