摘要
目的比较神经病理性疼痛大鼠模型脊髓背角中神经型（nNOS）、诱导型（iNOS）和内皮型（eNOS）三种一氧化氮合酶（NOS）的表达及活性变化。方法雌性SD大鼠20只，150～200g，随机均分为坐骨神经保留性损伤（SNI）组和对照组。SNI组大鼠于左后肢制备SNI模型，对照组大鼠暴露坐骨神经后立即缝合手术切口。术后观测疼痛的变化，于术后第14天断头处死大鼠，截取L4-6段脊髓，分离左右侧脊髓，于-80℃储存。SNI组和对照组各取5只大鼠脊髓，RT—PCR技术扩增nNOS、eNOS和iNOS片段，以β—actin作为内参照，比较SNI组与对照组NOS表达的相对差异。取两组另外5只大鼠脊髓冰上迅速匀浆，均取40μg的蛋白，分别检测组成型NOS（cNOS，即nNOS和eNOS）和iNOS的活性。结果SNI组手术侧nNOS、iNOS的mRNA表达均高于SNI组非手术侧和对照组手术侧（P＜0．05），而eNOS的表达在SNI组手术侧、非手术侧和对照组手术侧之间差异并无统计学意义。NOS亚型催化活性检测显示SNI组手术侧iNOs和cNOS的活性均高于SNI组非手术侧和对照组手术侧（P＜0．05）。结论神经病理性疼痛大鼠模型脊髓背角中iNOS的表达及其合成NO的活性均增加，可能促进了疼痛的发生，nNOS在疼痛中可能具有较强的调节能力。
Objective To determine the expression and activity of three main nitric oxide synthases （NOS） in spinal cord of rat with neropathic pain. Methods Twenty female SD rats were randomized into group SNI and control group with 10 rats each. The rats of control group had a sham surgery on the left hind limb. Group SNI had a partial lesion on the left sciatic nerve. After neuropathic pain developed,all rats were killed by cervical dislocation. L4-6 spinal cord segments were taken with the left and right side separated. Total RNA in 5 rats from each group was extracted and constitutive NOS（nNOS,eNOS） and inducible NOS（iNOS） were amplified with RT-PCR with β-actin as an internal standard. The left spinal cord segments were homogenized to extract protein for determination of total NOS, cNOS and iNOS activity. Results The ratios of nNOS and iNOS to β-actin on the operative side in group SNI were increased significantly compared to those on the operative side in control group and the no-operative side in group SNI（P〈0.05）. There was no marked difference in the ratio of eNOS to β-actin between control group and group SNI. The activity of iNOS and nNOS and eNOS on the operative side in group SNI increased significantly above that on the operative side in control group and the no-operative side in group SNI （P〈 0. 05）. Conclusion iNOS is increased in expression and activity in rat spinal cord following neuropathic pain, which may contribute to the development of neuropathic pain. nNOS may have a stronger ability of regulating the neuropathic pain.
出处
《临床麻醉学杂志》
CAS
CSCD
2008年第2期151-153,共3页
Journal of Clinical Anesthesiology
