Alderson K, Holds J B, Anderson R L
Department of Neurology, University of Utah School of Medicine, Salt Lake City 84132.
Neurology. 1991 Nov;41(11):1800-5. doi: 10.1212/wnl.41.11.1800.
To assess longstanding alterations in human muscle innervation induced by botulinum toxin, we studied motor axons in the orbicularis oculi of nine patients previously injected with botulinum toxin for treatment of benign essential blepharospasm (BEB). Compared with untreated BEB and normal orbicularis oculi, muscle exposed to botulinum toxin developed persistent and cumulative alterations of innervation, including (1) thin, unmyelinated axonal collaterals that contact muscle end plates, (2) an increased number of muscle fibers innervated by individual terminal motor axons, (3) a profusion of unmyelinated axonal sprouts that end blindly, (4) an increased range of end plate sizes, and (5) multiple end plates on individual muscle fibers. The findings suggest that axonal sprouts which develop after botulinum-toxin-induced functional denervation can form new end plates. A single muscle fiber may then be innervated at separate sites by more than one axon.
为评估肉毒杆菌毒素对人类肌肉神经支配的长期影响，我们研究了9例曾注射肉毒杆菌毒素治疗良性特发性眼睑痉挛（BEB）患者的眼轮匝肌运动轴突。与未经治疗的BEB患者和正常眼轮匝肌相比，暴露于肉毒杆菌毒素的肌肉出现了持续性和累积性的神经支配改变，包括：（1）接触肌终板的细的无髓轴突侧支；（2）单个终末运动轴突支配的肌纤维数量增加；（3）大量盲端的无髓轴突发芽；（4）终板大小范围增加；（5）单个肌纤维上有多个终板。这些发现表明，肉毒杆菌毒素诱导功能性失神经后形成的轴突发芽可形成新的终板。然后，单个肌纤维可能在不同部位由多个轴突支配。
