神经生长因子对下齿槽神经再生影响的实验研究

The influence of nerve growth factor on inferior alveolar nerves regeneration in the silicone tubes

目的 探讨外源性神经生长因子(nervegrowthfactor,NGF)对成年大白兔下齿槽神经再生的影响。方法 选用24只成年日本大耳白兔,在双侧下齿槽神经各造成8mm缺损,神经近远端用硅胶管桥接,右侧硅小室内注入外源性NGF作实验侧,左侧注入生理盐水为对照侧。对实验侧和对照侧的再生有髓神经纤维数目、传导速度、纤维横断面积和髓鞘厚度作相应比较。结果 ①NGF能使有髓神经纤维数目明显增加;②在术后相同时间,实验侧的有髓神经纤维横断面积和髓鞘厚度明显大于对照侧;③术后12周和18周时,实验侧再生神经传导速度明显大于对照侧。

Objective To explore the effect of exogenous nerve growth factor(NGF)in the regeneration of adult white rabbits inferior alveolar nerve within the silicone tubes. Methods In 24 adults white rabbits. A bilateral 8 mm inferior alveolar nerve gaps were created,and the proximal and distal stumps were inserted into a 12 mm silicone tube. The silicone tube of the right side was filled with exogenous NGF(experimental group)and the contralateral side was filled with saline (control group).Regeneration of the nerves was assessed by histological exam and nerve electrophysiological appreciation .Total number of the regenerating myelinated nerve fibers,the conduction velocities of nerves.the thickness of myelin sheaths and the cross section area of myelinated nerve fibers between the experimental and the control groups were compared. Results The results showed that: ①The experimental groups demonstrated more myelinated nerve fibers than that of the controls in 12 and 18 weeks.②At the same time following surgery,the myelin sheath thickness and the cross section area of myelinated nerves in the experimental groups were significantly greater than that in the controls.③In 12 and 18 weeks,the conduction velocities of regenerating nerves in the experimental groups were faster than that of the controls. Conclusion This study suggested that exogenous NGF can enhance regeneration of inferior alveolar nerve with recovery of its sensory function.