Department of Radiology, Chongqing The Seventh Peoplés Hospital, Chongqing, China.
Department of Radiology, Hainan Women and Children's Medical Center, No. 15, Long Kun Nan road, Haikou, Hainan 572500, China.
J Clin Neurosci. 2020 Nov;81:113-119. doi: 10.1016/j.jocn.2020.09.015. Epub 2020 Oct 5.
The spatial and temporal distribution of aquaporin-4 (AQP4) expression in rat brain following brain trauma and AQP4-siRNA treatment, as well as corresponding pathological changes, were studied to explore the mechanism underlying the effect of AQP4-siRNA treatment on traumatic brain injury (TBI). The rats in the sham operation group had normal structure, with AQP4 located in the perivascular end-foot membranes and astrocytic membranes in a polarized pattern. The accelerated polarity reversal was observed in the TBI group in 1-12 h after TBI. During this period, AQP4 abundance on the astrocytic membrane is gradually increased, while AQP4 abundance on the perivascular end-foot membrane declined rapidly. Twelve hours after TBI, AQP4 expression was depolarized, showing a shift from the perivascular end-foot membrane to the astrocytic membrane. Pathological observation showed that vasogenic edema occurred immediately after TBI, at which time the extracellular space was expanded, leading to severe intracellular edema. AQP4-siRNA reduced the polarity reversal index at the early stage of TBI recovery and reduced edema, demonstrating the potential benefit of reduced AQP4 expression during recovery from TBI.
研究创伤性脑损伤（TBI）后大鼠脑水通道蛋白-4（AQP4）表达的时空分布及 AQP4-siRNA 治疗的相应病理变化，探讨 AQP4-siRNA 治疗对 TBI 作用的机制。假手术组大鼠结构正常，AQP4 位于血管周足膜和星形胶质细胞膜上呈极化分布。TBI 后 1-12 h，TBI 组可见 AQP4 极性加速逆转，此时星形胶质细胞膜上 AQP4 含量逐渐增加，而血管周足膜上 AQP4 含量迅速下降。TBI 后 12 h，AQP4 表达去极化，从血管周足膜转移到星形胶质细胞膜。病理观察显示，TBI 后即刻发生血管源性水肿，此时细胞外空间扩张，导致严重的细胞内水肿。AQP4-siRNA 降低了 TBI 恢复早期的极性反转指数，减少了水肿，表明在 TBI 恢复过程中降低 AQP4 表达具有潜在益处。
