Oxidative stress following traumatic brain injury in rats
Oxidative stress following traumatic brain injury in rats
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DOI：
10.1016/s0090-3019(96)00461-2
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发表时间：
1997-06-01
影响因子：
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通讯作者：
Pryor, WA
中科院分区：
文献类型：
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作者：
Awasthi, D;Church, DF;Pryor, WA
背景自由基可能通过神经血管结构的氧化损伤参与创伤性脑损伤（TBI）的病理生理学。内源性抗氧化剂，如抗坏血酸和α-生育酚，可能在对抗这些氧化反应中发挥关键作用，其氧化产物可以作为氧化应激的重要指标。方法我们使用电子自旋共振（ESR）光谱和体内自旋捕获（有机化合物与自由基物质的反应）来检测TBI后可能产生的自由基。头部坠落技术造成伤害（5.1 公斤-厘米）。在 TBI 或假伤前立即向大鼠静脉注射 1 mL、0.1 M 自旋捕获器、α-苯基-N-叔丁基硝酮 (PBN) 或等体积的盐水。将动物分为四组：(1)组I：注射PBN假受伤，(2)组II：注射PBN受伤，(3)组III：注射盐水假受伤，和(4)组IV：注射盐水受伤。其他组的注射盐水的未受伤动物、注射盐水的动物和注射PBN的受伤动物用于组织病理学。 TBI 或假伤后 60 分钟，再次将大鼠麻醉并斩首。 1 分钟内取出大脑，均质化并提取脂质。通过ESR光谱分析提取物。使用抗坏血酸氧化酶测定法，通过分光光度法测定脑抗坏血酸 (AA) 浓度。 结果 TBI 后 60 分钟未观察到 PBN 自旋加合物信号（表明捕获的自由基物质）。所有组的大鼠均显示抗坏血酸自由基信号。然而，受伤大鼠的抗坏血酸信号强度（AI）显着较高，而大脑（AA）则显着降低。此外，在受伤动物中，AI/AA 的比率（消除大脑中不同抗坏血酸浓度的影响）也显着较高。结论我们得出结论，TBI 后 60 分钟，大脑中的氧化应激水平显着增加。这可能反映了自由基物质的形成以及随后在 60 分钟期间与抗坏血酸（抗氧化剂）的相互作用。 TBI 后 1 小时缺乏 PEN 自旋加合物信号可能表明自由基的产生是时间依赖性的，并且可能在 60 分钟之前或之后检测到。 (C) 1997 年，爱思唯尔科学公司。
BACKGROUNDFree radicals may be involved in the pathophysiology of traumatic brain injury (TBI) through oxidative damage of neurovascular structures. Endogenous antioxidants, such as ascorbate and alpha-tocopherol, may play a critical role in combating these oxidative reactions and their oxidized products can serve as an important index of oxidative stress.METHODSWe used electron spin resonance (ESR) spectroscopy and in vivo spin trapping (reaction of an organic compound with free radical species) to detect the possible generation of free radicals after TBI. Injury was inflicted by a weight drop technique over the head (5.1 kg-cm). Rats were intravenously infused with either 1 mL, 0.1 M of the spin trap, alpha-phenyl-N-tert-butyl nitrone (PBN), or an equivalent volume of saline immediately before TBI or sham-injury. Animals were divided into four groups: (1) Group I: PBN-infused sham-injured, (2) Group II: PBN-infused injured, (3) Group III: saline-infused sham-injured, and (4) Group IV: saline-infused injured. Additional groups of saline-infused uninjured, salin-infused, and PBN-infused injured animals were used for histopathology. Sixty minutes after TBI or sham-injury, rats were again anesthetized and decapitated. The brains were removed within 1 minute, homogenized, and extracted for lipids. The extracts were analyzed by ESR spectroscopy. Brain ascorbic acid (AA) concentration was determined spectrophotometrically, using the ascorbate oxidase assay.RESULTSNo PBN spin adduct signals (indicating trapped free radical species) were visible 60 minutes after TBI. All groups of rats showed an ascorbyl free radical signal. The ascorbyl signal intensity (AI) was, however, significantly higher in the injured rats, while the brain (AA) was significantly reduced. In addition, the ratio of AI/AA, which eliminates the effect of variable ascorbate concentrations in the brain, was also significantly higher in the injured animals.CONCLUSIONSWe conclude that 60 minutes following TBI there was a significantly increased level of oxidative stress in the brain. This may reflect formation of free radical species with subsequent interaction with ascorbate (antioxidant) during the 60 minute period. The lack of PEN spin adduct signals 1 hour after TBI may indicate that free radical generation is time dependent and might be detectable earlier or later than the 60 minute period. (C) 1997 by Elsevier Science Inc.