Bramlett Helen M, Dietrich W Dalton
Department of Neurological Surgery, Neurotrauma Research Center, and The Miami Project To Cure Paralysis, University of Miami School of Medicine, P.O. Box 016960, Mail R-48, FL 33101, USA.
Acta Neuropathol. 2002 Jun;103(6):607-14. doi: 10.1007/s00401-001-0510-8. Epub 2002 Mar 20.
There is evidence for chronic atrophy after human head trauma, which may be associated with long-term functional deficits. However, using established models of traumatic brain injury (TBI) only limited data are available for clarifying the extent of progressive gray and white matter atrophy. In the present study, male Sprague-Dawley rats underwent moderate (2.01-2.21 atm) parasagittal fluid percussion brain injury ( n=7) or sham ( n=3) surgery and were killed at 1 year post TBI. Semiserial sections were obtained through the neuraxis and double stained with hematoxylin and eosin to demarcate gray matter structures and Luxol fast blue for white matter visualization. Both ipsilateral and contralateral volume measurements were obtained for the following structures: cerebral cortex, hippocampus, dentate gyrus, thalamus, lateral ventricle, external capsule, internal capsule, cerebral peduncle and corpus callosum. Quantitative assessment of ipsilateral gray matter structures from TBI rats revealed significant reductions in cerebral cortical area measurements posterior from the trauma epicenter compared to sham animals. Importantly, several white matter tracts exhibited dramatic atrophy. A comparison of TBI and sham groups demonstrated a significant ( P<0.05) decrease in the external capsule and cerebral peduncle volumes ( P<0.007). In addition, there was a significant volume expansion (533% of control) of the ipsilateral lateral ventricle ( P<0.03). These novel data emphasize the need to clarify the pathophysiology of progressive white matter damage after TBI and the development of therapeutic strategies to target white matter pathology.
有证据表明人类头部创伤后会出现慢性萎缩,这可能与长期功能缺陷有关。然而,使用已建立的创伤性脑损伤(TBI)模型,关于阐明渐进性灰质和白质萎缩程度的可用数据有限。在本研究中,雄性Sprague-Dawley大鼠接受中度(2.01 - 2.21个大气压)矢状旁流体冲击性脑损伤(n = 7)或假手术(n = 3),并在TBI后1年处死。通过神经轴获取半连续切片,并用苏木精和伊红双重染色以划定灰质结构,用Luxol固蓝染色以观察白质。对以下结构进行同侧和对侧体积测量:大脑皮层、海马体、齿状回、丘脑、侧脑室、外囊、内囊、大脑脚和胼胝体。对TBI大鼠同侧灰质结构的定量评估显示,与假手术动物相比,创伤震中后方的大脑皮层面积测量值显著减少。重要的是,几条白质束表现出明显萎缩。TBI组和假手术组的比较显示,外囊和大脑脚体积显著(P < 0.05)减小(P < 0.007)。此外,同侧侧脑室体积显著扩大(为对照组的533%)(P < 0.03)。这些新数据强调了阐明TBI后进行性白质损伤的病理生理学以及针对白质病变制定治疗策略的必要性。