醛糖还原酶在急性脊髓损伤中的表达及其抑制剂对脊髓细胞凋亡的影响

The expression of aldose reductase and therapeutic benefits of their inhibition in rats injuried spinal cord

目的观察醛糖还原酶（AR）在急性脊髓损伤中的表达和醛糖还原酶抑制剂（ARI）对脊髓细胞凋亡的影响。方法成年SD大鼠150只，随机分为3组：假手术对照组（Sham组，n=50只），脊髓损伤组（SCI组，n=50只），醛糖还原酶酶抑制剂（依帕司他片，唐林）组（ARI组，n=50只），每组大鼠分别分为3、12、24、48、72h5个时间点。假手术组只做椎板切除术，SCI组和ARI组采用Allen’s法制备大鼠脊髓冲击伤模型。苏木素-伊红（HE）染色观察脊髓组织病理变化，双抗体夹心法检测AR含量，原位末端转移酶标记（TUNEL）法检测脊髓组织凋亡。结果ARI组伤后3、12、24、48、72h损伤区内灰、白质结构破坏程度，空腔形成程度和炎性细胞浸润轻于同时间点的SCI组，假手术组未见到灰质和白质的破坏。Sham组3、12、24、48、72h脊髓组织中AR含量分别为（10．75±0．47）、（10．61±0．44）、（10．62±0．55）、（10．92±0．49）、（10．57±0．52）U／L，SCI组对应时间点AR含量分别为（12．17±0．65、（14．09±0．61）、（14．58±0．72）、（15．45±0．47）、（15．33±0．29）U／L，ARI组对应时间点AR含量分别为（10．84±0．21）、（12．70±0．47）、（12．84．±0．55）、（12．28±0．54）、（11．95±0．90）U／L，SCI组AR含量在各个时间点均明显高于Sham组和ARI组（P〈0．05），Sham组各时间点很少见到脊髓凋亡细胞，SCI组3、12、24、48、72h脊髓细胞凋亡率（％）分别为8．45±0．51、27．38±3．19、32．59±3．36、39．04±4．51、23．48±2．40，ARI组对应时间点脊髓细胞凋亡率（％）分别为8．21±0．52、18．69±1．63、22．64±2．18、25．61±3．53、16．48±2．23，SCI组脊髓神经元凋亡率在12、24、48、72h高于ARI组（P〈0．05）。结论脊髓损伤后AR的表达增高，ARI能降低脊髓神经元细胞的凋亡率。

Objective To discuss the expression of Aldose reductase in acute spinal cord injury and the effect of Aldose reductase inhibitor on spinal cell apoptosis. Methods One hundred and fifty SD a- dult rats were randomly assigned to sham group （n = 50） , acute spinal cord injury （n = 50） , Aldose redue- tase inhibitor （Epalrestat Tablets） group （n = 50） , each group is divided into five sub- groups（6,12,24, 48,72 h sub-groups）. In the sham group,only lamineetomy was applied; In the SCI group and the ARI group,the model were made by Allen＇s method. The pathological changes in injured spinal cord were ob- served with hematoxylin and eosin staining. The aldose reductase was detected by Elisa methods. The TdT- mediated dUTP nick end labeling （TUNEL） method was employed to determine neuronal apoptosis. Results After injury 6,12,24,48 and 72 h,the grey and white matter structure of damage area were damaged, with cavity forming and inflammatory cells infiltrating. The degree of ARI group was lighted than SCI group. The content of aldose reductase in the sham operation group after injury 3,12,24,48,72 h were （ 10.75 ± 0.47）,（10.61 ±0.44）,（10.62±0.55）,（10.92±0.49）,（10.57 ±0.52） U/L,the AR contents of SCIgroup at corresponding time were （12.17 ±0.65）,（14.09 ±0.61）,（14.58 ±0.72）,（15.45 ± 0. 47） , （ 15.33 ±0. 29） U/L,and the AR content of the ARI group at corresponding time were （ 10. 84 ± 0. 21 ）, （ 12. 70 ± 0. 47 ）, （ 12. 84 ± 0. 55 ）, （ 12. 28 ± O. 54 ）, （ 11.95 ± 0. 90） U/L. The AR content of the SCI group at each time point were significantly higher than the shame operation group and ARI group （ P 〈 0. 05 ）. The spinal cord apoptotic cells were rarely seen in the sham operation group at each time point. The apoptotic rates （%） of SCI group after injuried 3,12,24,48,72 h were were 8.45 ±0. 51,27.38 ±3.19, 32. 59 ± 3.36,39. 04 ± 4. 51,23.48 ± 2. 40, and the rates of the ARI group at corresponding time were 8.21 ± 0. 52,18.69 ± 1.63,22. 64 ±2. 18,25.61 ±3.53,16.48 ±2. 23. The neuron apoptosis rates of SCI group at 12,24 , 48and 72 h were higher than that of the ARI group （P 〈 0.05 ）. Conclusion After acute spinal cord injury the expression of the AR inereased,ARI may reduce the spinal cord neurons cell apoptosis.