“Type grouping” in skeletal muscles after experimental reinnervation
“Type grouping” in skeletal muscles after experimental reinnervation
复制标题
实验性神经支配后骨骼肌的“类型分组”
作者：
C. Karpati;W. Engel
组织化学技术在人类肌肉活检研究中的应用有助于避免骨骼肌的一些病理反应，而这些反应在常规染色的石蜡包埋组织中并不明显。1-4这些异常之一被称为“类型分组”，并被定义为“相同组织化学类型的纤维组比正常大得多”。。。由50-100或更多的纤维组成。通常，在组织化学混合的肌肉中，两种基本的组织化学纤维类型(类型1和类型2)在横截面上以马赛克图案混合在一起。在正常人肌肉中，紧密相连的类似组织化学类型的纤维数量不超过50个，通常少于15个。类型分组通常在慢性周围神经病患者的肌肉活检中观察到(图1)，在运动神经元病的晚期较少见。它被认为是“侧支发芽”神经再支配的标志。本文提出了一种实验模型，通过实验神经再支配，在豚鼠的组织化学混合肌肉中产生典型的类型分组。这一结果支持了侧支发芽至少是人类疾病分型的一种致病机制。
APPLICATION OF histochemical techniques to the study of human muscle biopsies has helped to eludicate a number of pathologic reactions of skeletal muscle that are not evident in routinely stained paraffin-embedded tissue.1-4 One of these abnormalities has been termed “type grouping” and defined as “groups of fibers of the same histochemical type much larger than usual . . . consisting of 50-100 fibers or more.”Z Normally, in histochemically mixed muscles, the two basic histochemical fiber types (types 1 and 2) are intermingled in a mosaic pattern when viewed in cross section. In normal human muscle the number of fibers of similar histochemical type in tight contiguity does not exceed 50 and is usually less than 15. Type grouping is commonly observed in muscle biopsies of patients with chronic peripheral neuropathies (Fig. 1) and somewhat less often in the advanced stage of motor neuron disease. It has been postulated to be a sign of reinnervation by “collateral sprouting.”Z In this paper we present an experimental model in which typical type grouping was produced in histochemically mixed muscles of the guinea pig by experimental reinnervation. The results support the suggestion that collateral sprouting is at least one pathogenic mechanism which may be responsible for type grouping in disease in human beings.