嗅鞘细胞移植对大鼠脊髓损伤后水通道蛋白-4的影响

目的：探索大鼠嗅鞘细胞（olfactory ensheathing cells,OECs）移植对大鼠脊髓损伤（spinal cord injurySCI）后水通道蛋白-4（AQP-4）和后肢功能的影响。方法：取Wistar大鼠150只,随机分为正常组（50只）、模型组（50只）、OECs移植组（50只）,模型组和OECs移植组用改良的Allen法制成脊髓损伤模型,造模成功后,其中OECs移植组在损伤处移植嗅鞘细胞,模型组移植DF-12培养液。于术后1、3、7、14、21、28 d进行BBB（Basso-Beattle-Bresnahan）运动功能评分,应用免疫组织化学技术检测脊髓组织AQP-4的表达,并用图像分析仪进行定量分析。结果：术后3~28 d,OECs移植组的BBB评分较模型对照组明显提高,术后第1天,模型组和OECs移植组受损脊髓灰质、白质中AQP-4的表达明显增加;第3天时均达到高峰,但OECs移植组低于模型组（P〈0.05）。第7、14、21、28天,与模型组比较,OECs移植组AQP-4表达也较低（P〈0.01）。结论：OECs移植使脊髓损伤后AQPa表达减少，这可能有利于抑制脊髓水肿、消除脊髓继发性损伤，保存残存正常脊髓组织并促进神经轴突再生，改善其肢体运动功能。

Effect of Olfactory Sheath Cell Transplantation on Water Channel Aquaporin-4 in Rats with Experimentally Injured Spinal Cord

Objective： To investigate effects of transplanted olfactory sheath cells （OSC） on the water channel aquaporin-4 （AQP-4） expression and function recovery of hind limbs in rats with experimentally injured spinal cord. Methods： One hundred and fifty Wistar rats were randomly divided into normal group （group N）, model group （group M） and OSC transplantation group （group OSC）, with 50 rats in each. Modified Allen method was used to establish spinal cord injury model in groups M and OSC. OSCs were transplanted into the transected site of spinal cord in group OSC, while DF-12 solution was given into that of group M after the spinal cord injury model was made successfully. On the 1^st , 3^rd, 7^th, 14^th, 21^st , and 28^th days after the injury, the hind limb function of rats were estimated with system of BBB locomotion score, and the AQP-4 expression in spinal cord tissue was determined by immunohistochemistry technique and quantity analyzed with image analyzer. Results： From day 3 to day 28, the BBB locomotion scores of group OSC was higher than those of group M （P 〈 0. 05 ）. AQP-4 expression in gray matter and white matter of spinal cord was significantly increased in groups M and OSC on day 1 after the injury, and reached the peaks on day 3. The peak value of group OSC was significantly lower than that of group M （P〈0.05）, and so were other values on days 7, 14, 21, and 28 （P 〈0.01）. Conclusions： AQP-4 expression decreases after the transplantation of OSCs in injured spinal cord which might benefitthe inhibition to spinal cord edema and alleviation of secondary lesion. In this way OSC transplantation can protect the remained normal spinal cord tissues, promote the regeneration of axons, and enhance the recovery of locomotion function.