国际麻醉学与复苏杂志   2015, Issue (10): 3-3
    
骨癌痛大鼠脊髓背角酸敏感离子通道1a表达的变化
马文文, 朱珊珊1()
1.徐州医学院
Changes in expressions of acid-sensing ion channel 1a in spinal cord in a rat model of bone cancer pain
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摘要：

【摘要】目的 探讨骨癌痛（bone cancer pain，BCP）大鼠脊髓背角酸敏感离子通道1a（acid-sensing ion channel 1a，ASIC1a）表达的变化。方法 雌性未交配Srague-Dawley(SD)大鼠56只，体重180～220g，采用随机数字表法随机分为3组：正常组（I组，n=12），假手术组（II组，n=12）和BCP组（III组，n=32）。每组随机取8只分别于术前1d、术后第3，5，7，10，14，18天时测定大鼠体重和机械缩足反射阈值（paw withdrawal mechanical threshold，PWMT）。I组、II组于术后18d测完PWMT后，III组于术前1d，术后3，7，10，14，18天同一时段随机处死4只，取腰段脊髓，采用Western blot法检测ASIC1a的表达。每组于14天取4只大鼠，采用免疫荧光技术观察各组大鼠患侧脊髓ASIC1a和神经元免疫反应阳性产物的共表达。结果 与I、II组比较，III组术后第7～18天体重降低（P<0.01），术后第5d PWMT[（8.86±2.49）g]开始下降（P<0.01），术后7d PWMT[（5.17±1.26）g]，10d PWMT[（2.68±0.60）g]，14d PWMT[（1.85±0.98）g]，18d PWMT[（1.58±0.38）g]进一步降低（P<0.01）；Western blot显示，III组术后第3天开始ASIC1a表达上调（P<0.01），于术后第14～18d达到高峰（P<0.01）；免疫荧光发现，III组脊髓背角ASIC1a的表达显著增加（P<0.01），与神经元共标细胞数也相应增加（P<0.01）。结论 BCP大鼠脊髓背角神经元中ASIC1a表达增多，大鼠BCP的形成和维持可能与脊髓背角ASIC1a表达上调有关。
关键词： 骨肿瘤；疼痛；离子通道；脊髓
Abstract:

【Abstract】Objective To investigate the role of acid-sensing ion channel 1a (ASIC1a) in the spinal cord in a rat model of bone cancer pain. Methods 56 female Sprague-Dawley (SD) rats weighting 180-220g were randomly divided into 3 groups: normal group (group I, n=12), sham operation group (group II, n=12), bone cancer pain group (group III, n=32). Body weight and paw withdrawal mechanical threshold (PWMT) of mechanical stimulus with von-Frey filaments were determined the day before operation and at days 3,5,7,10,14 and 18d after operation. Four animals were killed randomly at 18d after operation in group I and II and at 3,7,10,14 and 18 d after operation in group III. The lumbar segments of the spinal cord was removed for determination of ASIC1a expression (by Western blot). Four animals were sacrificed on the 14th day after operation, the L4-L6 spinal cord segments were removed to measure the expressions of ASIC1a and the colocalization of ASIC1a and Neuronal nuclei (NeuN) in the dorsal horn by immunofluorescence staining. Results Paw withdrawal mechanical threshold (PWMT) to von-Frey filament stimulation were significantly decreased at 5d [(8.86±2.49)g], 7d [(5.17±1.26)g], 10d [(1.85±0.98)g], 18d [(1.58±0.38)g] after operation (P<0.01) whereas body weight difference were increased in group III at 7-18d as compared with group I and II (P<0.01). Compared with group I and II, ASIC1a expression in spinal cord of group III was significantly increased from day 3-18 after operation (P<0.01), and reached its peak on day 14-18d (P<0.01). Image of immunofluorescence showed increased-ASIC1a concentrated in the superficial laminae (I and II) in the spinal dorsal horn ipsilateral to hind paw of bone cancer pain rats (P<0.01). Double staining showed that ASIC1a was colocalized with NeuN and the number increased on day 14 after operation (P<0.01). Conclusion Expressions of ASIC1a were up-regulated in the superficial dorsal horn neurons of spinal cord in BCP rats. ASIC1a in the spinal cord may be involved in the mechanism of bone cancer pain in rats.
Key words: Bone neoplasms; Pain; Ion channels; Spinal cord