失面神经支配后豚鼠口轮匝肌线粒体和琥珀酸脱氢酶活性变化

The alteration of mitochondria and succinate dehydrogenase activity in musculus orbicularis oris of facial nerve denervated guinea pig

目的探讨不同程度面神经失神经支配对口轮匝肌及线粒体琥珀酸脱氢酶(SDH)活性的影响。方法制造颞骨外面神经麻痹豚鼠模型,在压榨程度相同条件下分为面神经压榨15S组、30S组,再分为观察7d组、30d组。SDH染色后,应用计算机图像分析系统进行各组纤维SDH酶含量测定,并观察线粒体结构和SDH酶阳性反应产物的变化。并应用瞬目反射方法测试15S组、30S组瞬目反射恢复时间。结果15S7d组I型和Ⅱ型SDH酶呈色反应较正常组明显减弱(P<0.01),30S7d组比15S7d组SDH酶活性显着性减弱(P<0.01)。15S7d组线粒体嵴少量断裂,SDH酶阳性反应颗粒轻度减少;15S30d组基本恢复正常。30S7d组线粒体嵴多量嵴断裂,SDH酶阳性反应颗粒重度减少;30d组线粒体结构和SDH酶反应颗粒轻度恢复。瞬目反射15S组恢复正常需要(36±12)d;30S组半年内未见恢复到正常。结论面神经受损伤持续时间越长,失神经支配程度越重,肌纤维及线粒体病变越重,肌功能恢复越慢,建议应早期行面神经减压术。

Objective To explore the influence of facial nerve denervation on the mitochondria and succinate dehydrogenase（SDH）activity in musculus orbicularis oris of guinea pig.Methods Facial nerve denervation models were made by compression of temporal bone externally for fifteen seconds（15s）or thirty seconds（30s）,the animals were fed for seven days（7d）or thirty days（30d）.Musculus orbicularis oris was obtained and stained by SDH staining,SDH content in musculus orbicularis oris was analyzed by computerized analysis system,and the ultrastructure of mitochondria was observed under trasmission electon microscope.And then the blink reflex recovery time of 15s and 30s was tested by the method of blink reflex.Resulrs The type Ⅰ and typeⅡSDH color fibers were obviously weakened in 15s7d group than in normal group（P〈0.01）,the SDH activity in 30s30d group was significantly weaker than that in 15s7d group（P〈0.01）.Less broken mitochondria crista and SDH positive reaction granules were found in 15s7d group,but 15d later recovered basically.Much less broken mitochondria crista and SDH positive reaction granules were seen in 30s7d group,while almost recovered to normal 15d later.Complete recovery of blink reflection needs（36±12）days in 15s group,but half a year later still not recovered completely in 30s group.Conclusion The longer the compression of facial nerve is,the more severe the damage of muscular fibers and mitochondria is,which suggests that decompression of facial nerve should be performed as early as posiblr.