Spontaneous recovery of lost motor functions is relative fast in rodent models after inducing a very mild/moderate spinal cord injury (SCI), and this may complicate a reliable evaluation of the effectiveness of potential therapy. Therefore, a severe graded (30 g, 40 g and 50 g) weight-compression SCI at the Th9 spinal segment, involving an acute mechanical impact followed by 15 min of persistent compression, was studied in adult female Wistar rats. Functional parameters, such as spontaneous recovery of motor hind limb and bladder emptying function, and the presence of hematuria were evaluated within 28 days of the post-traumatic period. The disruption of the blood-spinal cord barrier, measured by extravasated Evans Blue dye, was examined 24 h after the SCI, when maximum permeability occurs. At the end of the survival period, the degradation of gray and white matter associated with the formation of cystic cavities, and quantitative changes of glial structural proteins, such as GFAP, and integral components of axonal architecture, such as neurofilaments and myelin basic protein, were evaluated in the lesioned area of the spinal cord. Based on these functional and histological parameters, and taking the animal’s welfare into account, the 40 g weight can be considered as an upper limit for severe traumatic injury in this compression model.

在啮齿动物模型中，在诱导非常轻度/中度脊髓损伤 (SCI) 后，失去运动功能的自发恢复相对较快，这可能会使对潜在治疗有效性的可靠评估变得复杂。因此，在成年雌性 Wistar 大鼠中研究了 Th9 脊柱节段的严重分级（30 g、40 g 和 50 g）重量压缩 SCI，包括急性机械冲击和 15 分钟的持续压缩。在创伤后 28 天内评估功能参数，例如运动后肢和膀胱排空功能的自发恢复以及血尿的存在。在 SCI 后 24 小时检查血脊髓屏障的破坏，通过外渗的伊文思蓝染料测量，此时出现最大渗透性。在生存期结束时，评估了与囊腔形成相关的灰质和白质的降解，以及神经胶质结构蛋白（如 GFAP）和轴突结构的组成部分（如神经丝和髓鞘碱性蛋白）的数量变化。脊髓。基于这些功能和组织学参数，并考虑到动物的福利，40 g 的重量可以被认为是该压缩模型中严重创伤性损伤的上限。