促红细胞生成素早期治疗大鼠脊髓挫伤的形态学研究

Study on the morphology of spinal cord contusion injury rats by early treatment with erythropoietin

目的:研究促红细胞生成素(EPO)早期治疗大鼠脊髓挫伤的形态学与行为学改变。方法:采用BenchmarkTM颅脑损伤撞击器制备大鼠脊髓挫伤,并在伤后30min腹腔注射重组人红细胞生成素(5000UI.kg-1.BW)或者生理盐水。斜板试验和BBB评分法评价动物后肢运动功能。采用Harris氏HE染色法结合尼氏染色、Luxol固蓝染色观察损伤组织的形态学改变。应用血常规和血液流变学监测红细胞增生作用。结果:EPO组随着训练天数的增加,大鼠在斜板上维持的角度和BBB评分逐渐增大,与模型组比较有统计学差异(P<0.05)。伤后7、14、28d,脊髓损伤中心及邻近部位囊腔区域面积明显减小;距损伤中心前后3、5mm处灰质部前角神经元存活数量较多,与模型组比较有统计学差异(P<0.05)。伤后14、28d,脊髓损伤中心及前后3、5mm处髓鞘面积均显著高于模型组(P<0.05)。伤后红细胞计数,血红蛋白含量和红细胞压积均呈逐渐上升趋势。伤后14d开始,全血低切黏度、中切黏度有显著提高,与模型组比较有统计学差异(P<0.05)。结论:早期EPO治疗可能通过促进神经元存活、减少髓鞘脱失而减轻继发性损伤,最终改善后肢运动功能,但是增加了血源性不良反应的风险。

AIM. To study the morphological and behavior changes of spinal cord contusion rats by early treatment with erythropoietin （EPO）. METHODS. Spinal cord contusion inju- ry model in rats was duplicated with a Bench- markTM stereotaxic cortical impactor. Posttrau- matic 30 rain, animals were administrated by 5000UI· kg^-1 · gw recombinant human eryth- ropoietin or equal volume of saline through in- traperitoneal injection. The inclined plane test and BBB scale were used to assess the hindlimb motor function. Morphological changes were in- spected by using the Harris HE staining method combining with Luxol fast blue staining and Nissl staining. Blood routine test and hemorheo- logy were to monitor the effect of erythrocytic hyperplasia. RESULTS. With the increase in training days the angle sustaining on the inclined plane and BBB scores of EPO group were signifi- cantly higher than that of model group （P〈 0.05）. Posttraumatic 7, 14, 28 days the cavity size of injured center and adjacent parts in EPO group were significantly reduced. The numbers of survival neuron in the bilateral anterior horn of gray matter at 3 mm, 5 mm rostral and cand- ual to the injury site in EPO group were statisti- cally more than those in model group （P 〈 0.05）. Posttraumatic 14 and 28 days the LFB- positive area at injured site and 3ram, 5mm ros- tral and candual to epicentre in EPO group were significantly higher than those in model group （P〈0.05）. After injury the red blood cell count, hemoglobin and hematocrit showed a clear gradual upward trend. From posttraumatic 14 days the whole blood low-shear viscosity, middle-shear viscosity significantly increased compared with the model group （P 〈 0.05）. CONCLUSION： Early treatment with EPO may promote neuronal survival and reduce the loss of myelin sheath to mitigate secondary damage, and ultimately improve the hindlimb motor func- tion, but increased the risk of hematogenic ad- verse reactions.