SODIUM MRI OF DIFFUSE AXONAL INJURY IN A MINIATURE PIG MODEL

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 细胞主动地维持细胞内和细胞外钠浓度的梯度 车厢。这种浓度梯度对许多正常细胞至关重要 功能，以及高能耗的维护费用使其敏感地受到 很多病态。最近发现，轴突损伤可导致钠通道 (NACH)功能障碍和持续性轴索Na+内流。因为它能够敏感地 确定河流的空间分布、运动特征和局部环境。 在活体钠核中，我们认为钠磁共振成像(MRI)是一种独特的 弥漫性轴索损伤的无创性诊断和监测 钠处理的变化发生在病理早期，并持续到整个过程。 我们目前正在研究大脑钠信号强度的变化，这是一种特征良好的 小型猪弥漫性轴索损伤模型。 在旋转损伤前后采集小型猪的质子和钠图像。 钠图像被归一化为外部琼脂标准模体或自平衡图像 已知钠浓度的内部隔室(如玻璃体、脑脊液) 然后与质子图像共同配准。使用感兴趣区域(ROI)分析来比较 损伤前和损伤后的钠信号强度。我们建议将会有 受伤前和受伤后状态之间的信号强度显著变化，特别是 在被认为是最严重损伤的脑白质中。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cells actively maintain a gradient in sodium concentrations between the intracellular and extracellular compartments. This concentration gradient is critically important to a host of normal cellular functions, and the high energetic expense of its maintenance causes it to be sensitively affected by many pathologies. It has recently been discovered that axonal trauma can lead to sodium channel (NaCh) dysfunction and persistent axonal Na+ influx. Because it is capable of a sensitive determination of the spatial distribution, motional characteristics, and local environment of the sodium nucleus in vivo, we propose that sodium magnetic resonance imaging (MRI) is a uniquely suitable technique for noninvasive diagnosis and monitoring of diffuse axonal injury due to the changes in sodium handling that occur early in the pathology and persist throughout its course. We are currently investigating changes in brain sodium signal intensity in a well-characterized miniature pig model of diffuse axonal injury. Proton and sodium images of the minature pig are acquired before and after rotational injury. Sodium images are intensity normalized to external agarose standard phantoms or to homeostatic internal compartments with known sodium concentrations (e.g. vitreous humor, cerebrospinal fluid) and then coregistered to the proton images. Region-of-interest (ROI) analysis is used to compare sodium signal intensities in the pre- and post-injury states. We propose that there will be significant changes in the signal intensity between the pre- and post-injury states, particularly in brain white matter where the most substantial injury is thought to occur.