眼外肌注射A型肉毒毒素后神经萌芽及运动终板的变化  

The change of nerve sprouts and motor endplate after BTXA injection into extraocular muscle

作　　者：闫丽娟[1] 吴晓[1] 李鑫[1] 刘刚[1] 

机构地区：[1]首都医科大学附属北京同仁医院眼科中心,100730

出　　处：《眼科》2006年第5期326-330,共5页Ophthalmology in China

摘　　要：目的研究兔眼外肌注射A型肉毒毒素(BTXA)后3个月的神经末梢萌芽、运动终板及肌纤维的变化,从神经再生方面探讨BTX的作用规律。设计实验性研究。研究对象10只新西兰大白兔。方法10只白兔,在双眼8条眼外肌肌腹各注射BTXA 2．5U,在注射0、2、4、6、8、12周时各取一条眼外肌,共60条作乙酰胆碱酯酶(AchE)组化染色显示运动终板、肌纤维,用Bielschowsky银染法显示神经末梢萌芽。主要指标有萌芽终板数,总终板数；萌芽平均总长度/有萌芽终板数；运动终板的灰度值、面积；肌纤维直径。结果眼外肌的运动终板中,有萌芽终板数,总终板数、萌芽平均总长度/有萌芽终板数在2周(84．04±3．56．170．71±46．83)和4周(91．52±4．13,162．11±56．19)时达到最高峰,之后逐渐降低,到12周时降到最低(19．53±4．00,40．46±6．47),但仍稍高于正常值。运动终板的灰度值、面积及肌纤维直径亦出现此规律。结论注射BTXA后的神经末梢萌芽和运动终板的变化在2～4周时最为明显,之后逐渐降低,与临床上观察到的肉毒毒素作用规律相符,为研究肉毒毒素引起的肌麻痹的恢复过程提供一种新的观察途径。(眼科,2006．15：326-330)Objective To study the changes of nerve ends sprout, motor endplate and muscle fiber in 3 months after injection of botulinum toxin A （BTXA） into extraocular muscle, and from nerve regeneration discuss the action rule of BTXA. Design Experimental study. Participant 10 New Zealand rabbits. Method BTXA 2.5U were injected into bilateral eight extraoeular muscles of 10 New Zealand rabbits. After injection, at 0,2,4,6,8,12 weeks, picked out one extraocnlar muscle respectively, dyed with acetyleholinesterase to show motor endplate and muscle fibers, and with argentums（Ag） to show nerve sprouts. Main Outcome Measure The number of sprouts/ general endplate; The mean total length of sprouts/the number of sprouts; Grey and area of motor endplate; Diameter of muscle fiber. Result In the motor endplate of extraocular muscle, the number of sprouts/general endplate and the mean total length of sprouts/the number of sprouts reached the peak at 2 weeks and/or 4 weeks, then declined till 12 weeks, but still over the normal. Grey and area of motor endplate, diameter of muscle fiber showed the same vatting discipline. Conclusion VatTing of nerve ends sprout and motor endplate were the most obvious at 2 and/or 4 weeks after injection of BTXA, then decline gradually. It accords with the action discipline of BTX clinically, and offer a new observation approach for studying renews process of paralyzed muscle induced by BTX.

关 键 词：A型肉毒毒素 眼外肌 神经萌芽 运动终板 

分 类 号：R777.4[医药卫生—眼科]