【摘要】 目的　探索条件性损伤对脊神经根撕脱后脊髓前角运动神经元一氧化氮合酶 (NOS)表达及神经细胞死亡的影响。　方法　雌性 SD大鼠 78只 ,分为两组。实验组在臂丛神经干压榨术后 1周行神经根撕脱术 ;对照组仅施行神经根撕脱术。术后 3d～ 8周于不同时间点处死动物 ,取 C5 ～C8节段脊髓 ,行 NADPH- d组化染色 ,中性红复染。　结果　单纯神经根撕脱组术后第 5 d脊髓前角运动神经元开始表达 NOS,至术后 2周 NOS阳性神经元数达到高峰 ,3周后逐渐下降并伴有存活神经细胞的大量减少 ,术后 8周损伤侧存活神经细胞数为对照侧的 2 7.5 7% ;条件性损伤加神经根撕脱后 3d前角运动神经元开始表达 NOS,术后 2周达到高峰 ,随后 NOS阳性细胞逐渐减少并伴有神经细胞死亡 ,术后8周损伤侧存活神经细胞数为对照侧的 14.45 %。结论条件性损伤使脊神经根撕脱后前角运动神经元 NOS表达和神经元死亡时间提前 ,死亡数目增多。提示条件性损伤可能提前启动细胞的死亡机制更多还原

【Abstract】 Objective Investigate the effect of conditioning lesion on nitric oxide synthase (NOS) expression and cell death of spinal cord anterior horn motoneuron after spinal roots avulsion Methods Seventy eight adult Sprague Dawley female rats were divided into two groups In test group, the nerves of brachial plexus were clushed with microhemostatic forcep, then those nerval roots (C 5～T 1) were avulsed after a time span of a week The control group only received the surgery of spinal roots avulsion In a span from 3 days to 8 weeks, those two group animals were killed at different time The freeze sections of spinal cord were stained by NADPH d histochemistry and countersained by neural red Results In the control group, the spinal anterior horn motoneuron began to express NOS at the 5th day after avulsion and reached a maximum by 3 weeks after the lesion Then the NOS positive neurons gradually declined accompany with a significant motoneuron loss By 8 weeks the survival motoneurons were 27 57% of the intact side In conditioning lesion plus test lesion group, NOS positive motoneuron began to appear at the 3th day and reach a maxium by 2 weeks after spinal roots avulsion Then the NOS positive neurons began to decrease accompanied with motoneuron loss By 8 weeks, the survival motoneurons in lesion side were only 14 45% of the intact side Conclusions Conditioning lesion can advance the motoneuron nitric oxide expression and accelerate motoneuron death in the spinal roots avulsion model, which show that conditioning lesion may activize the death mechanism of spinal cord anterior horn motoneuron earlier更多还原