半乳凝素-1对脊髓损伤大鼠室管膜区细胞增殖的影响

Experimental study of the effects of Galectin-1 on proliferation of ependymal region cells in injured spinal cord of adult rats

目的：观察成年大鼠脊髓损伤后半乳凝素-1对室管膜区细胞增殖的影响，为进一步研究脊髓损伤后内源性神经干细胞的自身修复作用提供理论依据。方法：72只健康雌性SD大鼠，1．5月龄，体重190-220g，分为假手术组（A组）、模型组（B组）和治疗干预组（C组），每组24只。B、C两组均在T10节段制作急性脊髓损伤模型，A组仅行椎板切除。C组术后24h经枕大池蛛网膜下腔注入20μl（0．2g／L）半乳凝素-1，单次给药；其余两组仅给予等量的生理盐水。术后1d、7d每组进行后肢运动功能BBB评分，术后7d每组行免疫组织化学方法检测脊髓室管膜区BrdU和巢蛋白（Nestin）阳性细胞的表达变化情况。结果：术后1d后肢运动功能BBB评分A组为21．00±0．00分，B组为1．65±0．05分，C组为1．59±0．14分，B、C两组比较无显著性差异（P〉0．05）。术后7d后肢运动功能BBB评分，C组（12．98±0．15）、B组（6．38±0．21）与A组（21．00±0．00）比较均有显著性差异（P〈0．05）；C组与B组比较有显著性差异（P〈0．05）。术后7d，A组脊髓室管膜区免疫组化BrdU和Nestin阳性细胞相对值分别为0．02±0．01和0．01±0．00，仅见极少量；B组分别为0．41±0．14和0．35±0．13，与A组比较均明显增加（P〈0．05）；C组分别为1．02±0．25和0．88±0．20，均比B组增加更加明显（P〈0．05）。术后7d，A组脊髓室管膜区免疫组化BrdU和Nestin积分光密度值分别为17．12±3．47和10．59±2．11，B组（32．43±4．96，24．95±7．43）和C组（45．11±6．01，36．99±5．29）均高于A组（P〈0．05），但C组高于B组（P〈0．05）。结论：大鼠脊髓内室管膜区细胞具有潜在的增殖和分化能力，在损伤后该功能可被激活，半乳凝素-1对室管膜区细胞的增殖和分化具有明显促进作用。

Objectives： To observe the effects of Galectin-1 on the proliferation of cells in the ependymal region of injured spinal cord in adult rats, and to provide a theoretical basis for further study of endogenous neural stem cells in repairment of the injured spinal cord. Methods： 72 healthy female SD rats, with age of 1.5 months and body weight of 190-220g, were divided into sham group（group A）, model group（group B）, and intervention group（group C）. For the later two groups, spinal cord injury models were established on TIO, and for the sham group, only laminectomy was performed. The rats in treatment intervention group received sub- araehnoid injection of single dose of 20μl（0.2g/L） Galectin-1 24h after injury; the remaining two groups were only given normal saline. Neurological function recovery of the hindlimbs was evaluated using the BBB score 1 day and 7 days after injury, and the expression of BrdU positive cells and Nestin positive cells in spinal cord ependymal zone were detected using immunohistochemical method 7 days after injury. Results： The BBB score of group A was 21.00±0.00 one day after injury. The score of group B（1.65±0.05） showed no signifi- cant difference（P〉0.05） from that of group C（1.59±0.14） one day after injury. The BBB scores of group C （12.98±0.15） and B（6.38±0.21） were significantly different（P〈0.05） from that of group A（21.00±0.00） 7 daysafter injury; and the result was not significantly different between group C and B（P〈0.05）. 7 days after surgery, very little amount of BrdU positive cells（0.02±0.01） and Nestin positive cells（0.01±0.00） was found in group A; while the amount of BrdU positive cells（0.41±0.14） and Nestin positive cells（0.35±0.13） in group B were abun- dant and significantly increased（P〈0.05）; Increase in the amount of BrdU positive cells（1.02±0.25） and Nestin positive cells（0.88±0.20） in spinal cord ependymal zone in group C was significantly higher than group B（P〈 0.05）. 7d after operation, the BrdU and Nestin integral optical density value in group A were 17.12±3.47 and 10.59±2.11 respectively, group B（32.43±4.96, 4.96±7.43） and group C（45.11±6.01, 6.01±5.29） had higher value than group A（P〈0.05）, and group C was higher than group B（P〈0.05）. Conclusions： Cells in ependymal area of spinal cord display the potential of proliferation and neural differentiation after injury in rats. Galectin-1 promotes the proliferation and neural differentiation of the cells in this area.