Nishi Rebecca A, Liu Hongli, Chu Yong, Hamamura Mark, Su Min-Ying, Nalcioglu Orhan, Anderson Aileen J
CRF Spinal Cord Injury Core Research Facility, University of California, Irvine, California 92697-4540, USA.
J Neurotrauma. 2007 Apr;24(4):674-89. doi: 10.1089/neu.2006.0204.
This study characterized the Infinite Horizon (IH) Impactor for use in mouse models of contusion spinal cord injury (SCI), and investigated the feasibility and reliability of using magnetic resonance imaging (MRI) as a method to accurately measure lesion volume after mouse contusion SCI. Eight-week-old female C57Bl/6 mice received a mild (30 kilodyne), moderate (50 kilodyne), or severe (70 kilodyne) contusion injury at the T9 vertebral level. Uninjured control mice received a T9 laminectomy only. Functional recovery was assessed using the Basso, Beattie, Bresnahan (BBB) and Basso Mouse Scale (BMS) open-field locomotor rating scales. Next, 4% paraformaldehyde-perfused spinal cords were collected between the T6 and T12 spinal roots, and stored in phosphate-buffered saline (PBS) at 4 degrees C until MRI analysis. MRI lesion volumes were determined using T1-weighted images on a 7-Tesla MRI. Histology was performed on 20-microm polyester wax-embedded sections processed from the same spinal cords for stereological determination of fibronectin lesion volume and myelin basic protein spared white matter volume. Area of spared white matter at the epicenter was also analyzed. The results demonstrated that the IH Impactor produced precise, graded contusion SCI in mice. Lesion volumes were positively correlated with force of impact, and negatively correlated with spared white matter and functional recovery. Additionally, similar lesion volumes were detected using fibronectin staining and MRI analysis, although MRI may be more sensitive for milder injuries. These results give researchers more options in how to analyze spinal cord injuries in animal models.
本研究对用于脊髓挫伤性损伤（SCI）小鼠模型的无限视野（IH）撞击器进行了特性描述，并研究了使用磁共振成像（MRI）作为准确测量小鼠挫伤性SCI后损伤体积的方法的可行性和可靠性。8周龄雌性C57Bl/6小鼠在T9椎体水平接受轻度（30克力）、中度（50克力）或重度（70克力）挫伤性损伤。未受伤的对照小鼠仅接受T9椎板切除术。使用Basso、Beattie、Bresnahan（BBB）和Basso小鼠量表（BMS）旷场运动评分量表评估功能恢复情况。接下来，在T6和T12脊髓神经根之间收集用4%多聚甲醛灌注的脊髓，并保存在4℃的磷酸盐缓冲盐水（PBS）中，直至进行MRI分析。使用7特斯拉MRI上的T1加权图像确定MRI损伤体积。对从相同脊髓处理的20微米聚酯蜡包埋切片进行组织学检查，以立体测定纤连蛋白损伤体积和髓磷脂碱性蛋白保留的白质体积。还分析了震中处保留白质的面积。结果表明，IH撞击器在小鼠中产生了精确的、分级的挫伤性SCI。损伤体积与撞击力呈正相关，与保留的白质和功能恢复呈负相关。此外，尽管MRI对较轻损伤可能更敏感，但使用纤连蛋白染色和MRI分析检测到的损伤体积相似。这些结果为研究人员在如何分析动物模型中的脊髓损伤方面提供了更多选择。
