Ding Y, McAllister J P, Yao B, Yan N, Canady A I
Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI 48201, USA.
Neurol Res. 2001 Sep;23(6):581-7. doi: 10.1179/016164101101199045.
Motor and cognitive deficits are commonly associated with hydrocephalus. Although the mechanisms responsible for these impairments have not been confirmed, neuronal cell death and axon degeneration may play an important role, and have long lasting consequences on neuronal connectivity. The goal of this study was to determine if neural degeneration occurred during hydrocephalus in structures anatomically related to cognitive motor functioning, namely, the sensorimotor cortex, neostriatum, hippocampus and corpus callosum. Neural damage, as visualized by silver staining, was examined in adult rats 2-10 weeks after obstructive hydrocephalus was induced by kaolin injection into the cisterna magna. In mild or moderate hydrocephalus, mostly occurring 2-6 weeks after kaolin injections, silver-labeled axons were scattered in the white matter of the sensorimotor cortex, corpus callosum, neostriatum, and hippocampus. In severe hydrocephalus, 10 weeks after kaolin injections, axon degeneration was more extensive in these areas, as well as in layers IV through VI of the sensorimotor cortex. Axons in the subiculum and the fimbria were heavily labeled, suggesting damage to hippocampal afferent and efferent fibers. In contrast, neuron cell death was rarely observed at any stage of hydrocephalus. The major pathological change of brain regions involved in motor and learning functions during hydrocephalus is axon degeneration, and this degeneration is correlated with an enlargement of the cerebral ventricles.
运动和认知缺陷通常与脑积水有关。尽管导致这些损伤的机制尚未得到证实，但神经元细胞死亡和轴突退化可能起重要作用，并对神经元连接产生长期影响。本研究的目的是确定在脑积水过程中，与认知运动功能相关的解剖结构，即感觉运动皮层、新纹状体、海马体和胼胝体中是否发生神经退化。通过银染观察到的神经损伤，在成年大鼠经向大脑大池注射高岭土诱导梗阻性脑积水后2至10周进行检查。在轻度或中度脑积水（大多发生在高岭土注射后2至6周）中，银标记的轴突散在于感觉运动皮层、胼胝体、新纹状体和海马体的白质中。在严重脑积水（高岭土注射后10周）中，这些区域以及感觉运动皮层IV至VI层的轴突退化更为广泛。海马下托和穹窿中的轴突被大量标记，表明海马传入和传出纤维受损。相比之下，在脑积水任何阶段很少观察到神经元细胞死亡。脑积水期间参与运动和学习功能的脑区的主要病理变化是轴突退化，并且这种退化与脑室扩大相关。
