Facial Motor Nucleus Apoptosis And Extracranial Facial Never And Muscle Pathological Change After Extracranial Nerve Transection

Background The central nervous system (CNS) is very sensitive to traumatic injury and its capacity to regenerate is limited. Therefore, in most of cases, there is no or only incomplete repair following an insult causing delayed restoration and long-lasting or even persistent malfunction. Facial nerve nucleus, like other non-renewable cells, it can lead to the death of motor neurons after facial nerve injury. In order to understand better the mechanisms and limitations of CNS regeneration, deeper insights into the facial never neuronal cell apoptosis. It is one of the effective methods to establish facial nerve after peripheral facial nerve injury by animal model, which are recognized as "Kreutzberg model"[1].Johnson and Duberley [4] estimate that between 17% and 25% of the motoneurones undergo cell death following facial nerve transection in adult Wistar rats, respectively. Some investigators have attributed the rapid demise of motoneurones to apoptosis as terminal deoxynucleotidy transferase-mediated dUTP nick ends labeling (TUNEL) are positive[5, 6].Objective Its arm was pathological changes of facial nerve nucelus apoptosis expression and peripheral facial nerve and target muscle after rabbit facial nerve transection injury with the passage of time.Methods It was randomly selected one aspect of facial neural stem transaction model by random number of options 50 rabbits, which were divided into operated group and control group.It was observed pathological changes of facial nucleus apoptosis,peripheral facial nerve and target muscle after transaction injury Day 3,Day 7,Day 14,Month 1,Month 2 or Month 3, chosen left ventricular perfusion killing all rabbits at survival time, which were made of paraffins. Results All the 47 rabbits was entered the final analysis, it was observed facial nerve motor neuron apoptosis in different regions using Image Pro Plus 5.1 statistical software at HPF under fluorescence microscope. Facial nerve motor neuron apoptosis were significantly observed at Day 7 and Day 14 there were significant differences between Day 7or Day 14 and the control group facial nerve motor neurons apoptosis after facial nerve transection injury (p <0.05).The expression of NSE,MG,DES,NF,S-100,CgA,SMA and anothe protern were uesd to detect facial nerve or target muscle though tissue microarray immunohistochemical. NES might be regarded as more obvious by immunohistochemistry at Day 3,Day 7 and Day 14. Nerve axons shrink or even disappear at Month 1. MG was shown expression at each group of facial nerve target muscles after extra cranial facial nerve transection ,which were found band membrane thickening edema at Day 7,the band nutritional disorders at Month 1 and Month 2,loss of significant change facial muscles atrophy at Month 1.Conclusion The top expression of facial nerve motor neuron cell apoptosis can be seen after rabbits facial nerve transection injury at Day 14;the performanc of NSE could be detected as a reference phase of facial nerve acute injury for which had the same the peak period at Day 14 as facial nerve motor neuron apoptosis, Facial muscle changed slowerly about 14 days than that; peripheral facial nerve degeneration and regeneration coexist at Day 3; facial target muscles show shrink and apraxia after loss of facial muscle nutritional support were at Month 3. MG should be used as the detection regeneration function of facial muscles.The other protern could sought as no reference value.