Barron K D, Dentinger M P, Popp A J, Mankes R
Neurology Service, Veterans Administration Medical Center, Albany, New York.
J Neuropathol Exp Neurol. 1988 Jan;47(1):62-74. doi: 10.1097/00005072-198801000-00008.
Albino rats six weeks (wk) of age underwent transection of the spinal cord at the level of the seventh thoracic vertebra. They were killed ten wk later by several schedules of formaldehyde-glutaraldehyde, formaldehyde and formaldehyde-ethanol-acetic acid perfusion-fixation. Layer Vb of the sensorimotor cortex, the site of origin of corticospinal axons severed by the operation, was searched by light and electron microscopic methods for evidence of neuronal necrosis. Cord-transected rats were compared with control, unoperated animals of identical age. Nerve cell death was not evident to qualitative study, although shrunken, deeply-staining neurons of artefactitious origin occurred capriciously in paraffin sections when fixation was initiated with a dilute formaldehyde-glutaraldehyde solution. Quantitative light and electron microscopic studies were also negative for indications of neuronal death. However, mild somal atrophy could be substantiated for layer Vb neurons of cord-transected rats by light microscopic, morphometric methods. Neuronal atrophy was unaccompanied by qualitative or quantitative ultrastructural alterations. Subcellular organelles and the per cent of neuronal plasma membrane apposed by axosomatic boutons were unchanged. Neuroglia and neuronal processes always had a normal electron microscopic appearance.
六周龄的白化大鼠在第七胸椎水平进行脊髓横断。十周后，通过几种甲醛 - 戊二醛、甲醛以及甲醛 - 乙醇 - 乙酸灌注固定方案将它们处死。采用光镜和电镜方法，在感觉运动皮层的Vb层（手术切断皮质脊髓轴突的起始部位）寻找神经元坏死的证据。将脊髓横断的大鼠与同龄未手术的对照动物进行比较。定性研究未发现明显的神经细胞死亡，尽管在用稀释的甲醛 - 戊二醛溶液开始固定时，石蜡切片中偶尔会出现人为来源的萎缩、深染神经元。定量光镜和电镜研究也未发现神经元死亡的迹象。然而，通过光镜形态计量学方法可以证实，脊髓横断大鼠的Vb层神经元存在轻度的胞体萎缩。神经元萎缩并未伴有定性或定量的超微结构改变。亚细胞器以及轴体终扣所接触的神经元质膜百分比均未改变。神经胶质和神经元突起的电镜外观始终正常。
