Hu A-M, Li J-J, Sun W, Yang D-G, Yang M-L, Du L-J, Gu R, Gao F, Li J, Chu H-Y, Zhang X, Gao L-J
Capital Medical University School of Rehabilitation Medicine, Department of Spinal and Neural Function Reconstruction, China Rehabilitation Research Center, Beijing, China.
China Rehabilitation Research Center, Department of Neurosurgery, School of Rehabilitation Medicine of Capital Medical University, Beijing, China.
Spinal Cord. 2015 Feb;53(2):98-102. doi: 10.1038/sc.2014.209. Epub 2014 Dec 2.
Spinal cord edema contributes to the pathophysiological mechanisms underlying spinal cord injury (SCI) and is associated with functional recovery after SCI. Early myelotomy may be a promising surgical intervention for reducing SCI-induced edema. However, it remains unclear whether myelotomy can reduce SCI-induced edema. In addition, aquaporin-4 (AQP4) and aquaporin-9 (AQP9) have important roles in the regulation of water homeostasis. Here, we aimed to determine the effects of myelotomy on AQP4 and AQP9 expression and spinal cord edema in a rat model of moderate SCI.
Rats were randomly assigned to three groups: the sham control group (n=22) receiving laminectomy alone; the contusion group (n=44) receiving laminectomy plus contusion; and the myelotomy group (n=44) receiving laminectomy plus contusion followed by myelotomy at 24 h. Functional recovery was estimated by the open-field and inclined plane tests. Spinal cord edema was determined by measuring the water content. The expression of AQP4 and AQP9 was determined by western blot.
Compared with the contusion group, myelotomy significantly improved the Basso, Beattie and Bresnahan scores in the open-field test and resulted in a higher mean angle value in the incline plane test. Myelotomy significantly reduced SCI-induced edema at 4 and 6 days after SCI, which was accompanied by downregulation of AQP4 and AQP9 expression.
Myelotomy improves locomotor function, reduces edema in rats with SCI and is associated with decreased expression of AQP4 and AQP9.
脊髓水肿参与脊髓损伤（SCI）的病理生理机制，并与SCI后的功能恢复相关。早期脊髓切开术可能是一种有前景的减轻SCI所致水肿的手术干预方法。然而，脊髓切开术是否能减轻SCI所致水肿仍不清楚。此外，水通道蛋白4（AQP4）和水通道蛋白9（AQP9）在水稳态调节中起重要作用。在此，我们旨在确定脊髓切开术对中度SCI大鼠模型中AQP4和AQP9表达及脊髓水肿的影响。
将大鼠随机分为三组：假手术对照组（n = 22），仅接受椎板切除术；挫伤组（n = 44），接受椎板切除术加挫伤；脊髓切开术组（n = 44），接受椎板切除术加挫伤，然后在24小时进行脊髓切开术。通过旷场试验和斜面试验评估功能恢复情况。通过测量含水量确定脊髓水肿情况。通过蛋白质印迹法测定AQP4和AQP9的表达。
与挫伤组相比，脊髓切开术在旷场试验中显著提高了Basso、Beattie和Bresnahan评分，并在斜面试验中导致更高的平均角度值。脊髓切开术在SCI后4天和6天显著减轻了SCI所致水肿，同时伴有AQP4和AQP9表达下调。
脊髓切开术可改善SCI大鼠的运动功能，减轻水肿，并与AQP4和AQP9表达降低相关。
