马匹草病与骨神经肌肉结节的超结构重大异常有关
Bruce C McGorum1, Tracey Davey2, Miranda C M Dosi1
1Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Roslin, UK.
Equine veterinary journal
|February 1, 2024
概括
马匹草病 (EGS) 导致神经肌肉结节 (NMJs) 发生显著变化,与肉毒症不同. 这些NMJ变化表明,在EGS病例中,一种新型毒素准骨肌肉.
科学领域:
- 兽医神经学 兽医神经学
- 马类病理学 马类病理学
- 神经毒理学 神经毒理学
背景情况:
- 马草病 (EGS) 是一种致命的,多系统的神经病在马的原因不明.
- 关于EGS的建议病因包括Clostridium botulinum毒素感染或真菌毒素.
- EGS对神经肌肉结 (NMJ) 的影响,这是肉毒神经毒素 (BoNTs) 的关键部位,仍然没有特征.
研究的目的:
- 研究和比较马的骨NMJs的结构完整性和组织与EGS对照马.
- 为了区分EGS中的NMJ病理与在马类肉毒症中观察到的病理.
主要方法:
- 采用了一个盲目的,追溯的病例控制研究设计.
- 从隔膜或肋间肌肉样本的NMJs使用电子显微镜,形态测量和共聚焦光显微镜进行了分析.
- 从六匹EGS马,三匹对照马和一匹被证实患有马类肉毒的马身上采集了样本.
主要成果:
- 与对照组 (6.9%) 相比,EGS马的异常NMJ形态发生率显著更高 (72.2%) .
- EGS NMJs表现出降低的突触囊泡体积 (18.7%与对照中的36.3%相比),表明SV枯竭和加速的外细胞分裂.
- 在EGS NMJ中观察到神经纤维积累和结节退化的证据,与肉毒瘤病例中观察到的SV集群不同.
结论:
- EGS与骨NMJ超结构的深刻变化有关,与BoNT效应不同.
- 在EGS中SV枯竭表明一种影响神经传递的前突触毒素,可能是一种刺激性毒素或再吸收抑制剂.
- 骨NMJ被确定为马匹草病的致病原体的新目标.
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