Background: The research about anti-edema effects of mannitol on acute traumatic spinal cord injury (SCI) in rats is rare.

Objective: This study aimed to explore the effect of mannitol on spinal cord edema after SCI in rats.

Methods: Seventy-eight adult female rats were assigned to three groups randomly: a sham control group (n = 18), a contusion and normal saline contrast group (n=30), and a contusion and mannitol treatment group (n=30). We used the open-field test to estimate the functional recovery of rats weekly. Spinal cord water content was measured to determine the spinal cord edema. The ultrastructure features of the injured dorsolateral spinal cord were determined on the 7th day after SCI by HE staining.

Results: The mannitol group had greatly improved Basso-Beattie-Bresnahan (BBB) scores when compared with the saline contrast group. The spinal cord water content was increased significantly after SCI, and there was no significant difference in the water content between the NaCl and mannitol groups 1 day after SCI. The water content at 3 and 7 days after SCI was significantly lower in the mannitol group than in the NaCl group (p < 0.05). Mannitol can reduce spinal cord edema by increasing the number of red blood cells in the injured spinal cord and decrease the ratio (dorsoventral diameter/ mediolateral diameter) of spinal cord 7 days post-SCI.

Conclusion: Mannitol increases recovery of motor function in rats, reduces spinal cord edema and increases the number of red blood cells in the injured spinal cord, decreasing the ratio of spinal cord to reduce pressure.

背景：关于甘露醇对大鼠急性脊髓损伤（SCI）的抗水肿作用的研究很少。

目的：本研究旨在探讨甘露醇对脊髓损伤后脊髓水肿的影响。

方法：将78只成年雌性大鼠随机分为三组：假对照组（n = 18），挫伤和生理盐水对比组（n = 30）以及挫伤和甘露醇治疗组（n = 30）。 。我们使用露天试验来估计大鼠每周的功能恢复。测量脊髓水含量以确定脊髓水肿。在脊髓损伤后第7天，通过HE染色确定受伤的背外侧脊髓的超微结构特征。

结果：与盐水对比组相比，甘露醇组的Basso-Beattie-Bresnahan（BBB）得分大大提高。脊髓损伤后1天脊髓水含量显着增加，NaCl组和甘露醇组之间的水分含量无显着差异。甘露醇组在SCI后第3天和第7天的水含量明显低于NaCl组（p <0.05）。甘露醇可通过增加受损脊髓中的红细胞数量并降低脊髓损伤后7天脊髓的比例（腹侧直径/中外侧直径）来减少脊髓水肿。

结论：甘露醇可增加大鼠运动功能的恢复，减轻脊髓水肿，并增加受伤脊髓中的红细胞数量，降低脊髓比例以降低压力。