眼外肌注射肉毒杆菌毒素A后的形态学改变

Morphologic changes in extraocular muscles after injection botulinum A toxin

目的 进一步观察肉毒杆菌毒素A(BTA)所致的眼外肌形态学改变并探讨其作用机制。方法 用组化 3种方法 (HE染色 ,BEST卡红法 ,1%氯化金染色 )对注射BTA后不同时间的兔眼外肌行光镜下组织结构检查 ,并用透射电子显微镜观察其超微结构的变化。结果 注射BTA后 1周出现肌浆网的增多和扩张 ,线粒体的基质着色加深 ,肌糖原颗粒增多。注药后 1月眼外肌出现肌糖原纤维的节段性痉挛。注药后两月眼外肌出现不可逆萎缩。结论 BTA作用部位的眼外肌纤维出现节段性不可逆萎缩 ,随注药后时间的延长神经肌肉接头处神经再生 ,从而产生肌纤维的节段性增生 ,使眼外肌力得到部分或全部的恢复。

ObjectiveTo investigate the morphologic changes of the effect of botulinum toxin A(BTA) into extraocular muscles.MethodsHistochemical methods including hematoxylin and eosin stain and gold chloride stain were used to study the extraocular muscles of rabbits at different time period after BTA injection by light microscope.Ultrastructural changes were determined by electron microscopy.ResultsOne week after BTA injection,the amount of sarcoplasmic reticulum had expanded,and the basement color of the mitochondria and the amount of muscle glycogen increased.One month after injection,segmental myofibril spasm was seen.Two months after injection,the extraocular muscle became atrophic.ConclusionAt the site of the BTA injection in the muscle irreversible atrophy was found in segments, where the nerve terminals regenerate after injection,the myofibrils demonstrate focal hyperplasia in suggesting the muscle function will partly recover.