诱导型一氧化氮合酶反义核酸对脊髓损伤后神经功能的影响

目的　观察诱导型一氧化氮合酶反义核酸 (ASODN iNOS)对大鼠脊髓损伤 (SCI)后神经功能恢复的影响。方法　设计并合成ASODN iNOS ,微量注入大鼠蛛网膜下腔后制备成脊髓压迫伤动物模型 ,伤后 6h用逆转录 聚合酶链反应 (RT PCR)检测iNOSmRNA表达变化 ,2 4h后用分光光度法测定组织中一氧化氮 (NO)含量和一氧化氮合酶 (NOS)活性 ,4周后用电生理、动物行为学和病理学等指标评价神经功能的恢复情况。对照组为正常组、损伤对照组和无义核酸对照组 (NSODN)。结果　SCI后组织中存在iNOS的表达 ,应用ASODN iNOS可以抑制相应酶的表达 ,并可以降低组织中的NO含量和NOS活性 ,改善神经传导功能 ,与损伤对照相比差异有显著性 ,NSODN没有上述作用。结论　脊髓损伤后应用iNOS反义核酸可以使伤后神经功能得到改善。     

碱性成纤维细胞生长因子对牵张性脊髓损伤后一氧化氮合酶活性的影响

目的观察碱性成纤维细胞生长因子(bFGF)对牵张性脊髓损伤后一氧化氮合酶(NOS)活性的影响,探讨其对脊髓损伤的保护作用。方法大鼠脊髓T13~L2经牵张损伤,皮层体感诱发电位监测P1-N1波幅下降至术前波幅70%后,于损伤平面以下经蛛网膜下腔置细导管,治疗组分别于术后即刻0·5、1、2、3、4h经细导管注入bFGF溶液20μl(含bFGF20μg),对照组在相同时间注入等量生理盐水,采用放射强度测定法测定一氧化氮合酶(NOS)含量。结果正常组NOS活性为3·92±1·31,脊髓损伤后各时相点生理盐水组较正常组NOS活性显著增加,而bFGF治疗组NOS活性明显下降,与生理盐水组比较差异有显著性意义(P<0·01)。结论bFGF能够抑制脊髓损伤后NOS的活性,减轻脊髓继发性损害,从而保护脊髓组织。     

乙醇毒染大鼠睾丸总抗氧化能力、一氧化氮和一氧化氮合酶的变化与生殖细胞凋亡的关系

目的:探讨饮酒大鼠睾丸总抗氧化能力(T-AOC)、一氧化氮(NO)含量和一氧化氮合酶(NOS)活性的变化与生殖细胞凋亡的关系。方法:20只成年健康SD雄性大鼠随机均分为对照组和实验组,实验组和对照组分别用50%的乙醇溶液和蒸馏水按10 m l/kg每晚灌胃1次连续26 d(两个生精周期)后,用硝酸还原酶法测定睾丸组织中NO含量;用化学比色法测定其T-AOC和NOS活性;原位缺口末端标记(TUNEL)法检测生殖细胞凋亡指数(AI)的变化。结果:与对照组相比,实验组生殖细胞AI增加(P<0.01);睾丸组织T-AOC极显著下降(P<0.01),而NO含量明显上升(P<0.01)、NOS活性显著增强(P<0.01)。结论:大量饮酒能诱导生殖细胞凋亡增加,NOS活性增强导致NO的过量产生及T-AOC的显著下降是其重要原因。     

一氧化氮、一氧化氮合酶与伴精索静脉曲张不育患者精液参数的关系

目的:探讨一氧化氮(NO)、一氧化氮合酶(NOS)与伴精索静脉曲张(VC)不育患者精液参数之间的关系。方法:根据体格检查和彩色多普勒超声检查选择伴VC的不育患者(组1,n=53),其中临床型和亚临床型分别为21例和32例;同时选择非VC少弱精子症患者(组2,n=29)和正常生育者(组3,n=28)作对照组。采用硝酸还原法分别测定外周血和精浆中NO含量和NOS活性。用计算机辅助精液分析仪测定VC组患者精子密度、活动精子(a+b级精子)和快速前向运动精子百分率。结果:①组1外周血清NO含量和NOS活性与组2及组3相比差异无显著性(P>0.05),但精浆中NO含量和NOS活性组1明显高于其他两组,差异有显著性(P<0.01和P<0.05)。②组1中,随着曲张的精索静脉内径的增加,外周血清和精浆中NO含量和NOS活性均有所上升,但只有精浆中临床型和亚临床型之间相比差异有显著性(P<0.05)。③组1中,随着精子密度和精子活力的下降,外周血清和精浆中NO含量和NOS活性均有上升趋势,且精子密度≥20×106/ml和≤10×106/ml之间,精子活力≥50%和≤25%之间差异有显著性(P均<0.05)。结论:在VC诊断中精浆中NO含量和NOS活性测定较外周血清中更有意义。早期测定精浆NO含量和NOS活性对VC的诊断和治疗具有重要的临床价值。     

兔坐骨神经火器伤后腰段脊髓一氧化氮和一氧化氨合酶的变化及其意义

目的　探讨兔坐骨神经火器伤后腰段脊髓一氧化氮 (NO)含量和一氧化氮合酶(NOS)活性变化规律及在细胞凋亡发生中的作用。方法　大耳白兔 94只 ,火器伤组致伤靶点为兔右后肢外侧坐骨神经体表投影线中点 ,切割伤组在同一致伤水平切断坐骨神经 ,应用DNA电泳、原位末端标记法 (TUNEL)进行腰段脊髓细胞凋亡定性检测 ,流式细胞术进行定量检测 ,同时对腰段脊髓NO含量和NOS活性进行检测。结果　火器伤组 1周和 2周时 ,运动神经元和胶质细胞发生了凋亡 ,切割伤组 4周时有少量运动神经元发生凋亡。火器伤组 1、3d、1、2周时 ,脊髓NO含量显著升高 (P <0 .0 1 ) ;3d、1周、2周时 ,NOS活性升高 (P <0 .0 5 ,0 .0 1 )。结论　火器伤组细胞凋亡发生早、数量多 ,NO和NOS变化是其发生原因之一。     

一氧化氮(NO)在脊髓缺血再灌注损伤中作用的实验研究

目的　研究一氧化氮 (NO)在脊髓缺血再灌注损伤中的作用。方法　夹闭大鼠腹主动脉制成缺血再灌注模型 ,随机分成L -NAME组和再灌注组 ,L -NAME组每日腹腔注射一氧化氮合酶(NOS)非特异性抑制剂L -硝基精氨酸甲酯 (L -NAME) 10mg/kg体重 ,两周时取大鼠脊髓做NOS免疫组织化学染色、组织学及超微病理观察。结果　脊髓缺血再灌注后前角运动神经元出现固有型一氧化氮合酶 (cNOS)阳性表达 ,同时伴随前角运动神经元损伤 ;应用L -NAME后可减少cNOS的异常表达 ,减轻前角运动神经元损伤。结论　局部组织中NO产生增多可能是脊髓再灌注损伤的机制之一。     

烧伤大鼠小肠组织中两型一氧化氮合酶变化的观察

目的 研究烧伤后大鼠小肠组织中两型一氧化氮合酶的变化及与一氧化氮(NO)的关系。方法 采用30％TB-SAⅢ度烧伤大鼠模型,分别检测了小肠组织中NO含量及原生型NOS(cNOS)和诱导型NOS(iNOS)的活性,并分析了NO的变化规律及其与两型NOS之间的关系。结果 烧伤后小肠组中iNOS活性大幅上升,与NO的变化趋势一致,二者呈显著正相关(P<0.01),而cNOS活性呈下降趋势,与NO相关不显著(P<0.05)。结论 烧伤后小肠组织中NO的变化主要受iN-OS活性影响,iNOS活性上升,cNOS活性下降可能与烧伤后胃肠道病理变化密切相关。     

七氟烷麻醉对大鼠脑一氧化氮合酶活性和一氧化氮含量的动态影响

目的 观察七氟烷吸入麻醉不同时期大鼠大脑皮质、脑干、海马一氧化氮合酶(NOS)活性和一氧化氮(NO)含量的动态变化规律,以探讨脑区NOS和NO在七氟烷麻醉效应中的地位。方法SD大鼠随机均分为5组:对照组、诱导期组、麻醉期组、恢复期组和清醒期组。分光光度法测定不同时期各脑区NOS活性和NO含量变化。结果与对照组比较,诱导期大脑皮质、脑干、海马NOS活性分别降低34.8％、30.3％、30.0％,NO含量分别降低20.3％、21.0％、25.2％;麻醉期NOS活性和NO含量降至最低水平(P均<0.01),大脑皮质、脑干、海马NOS活性分别降低57.4％、56.6％、58.8％,NO含量分别降低41.5％、49.5％、44.7％;而恢复期又开始上升,但仍低于对照组水平,大脑皮质、脑干、海马NOS活性分别降低25.2％(P<0.05)、19.3％(P>0.05)、28.1％(P<0.05),NO含量分别降低28.3％、29.8％、26.2％(P均<0.01);清醒期NOS活性和NO含量基本恢复至对照组水平(P>0.05)。大鼠各脑区NOS活性和NO含量的改变与麻醉深度的变化有趋同性。结论七氟烷可明显抑制大鼠大脑皮质、脑干、海马NOS活性和降低NO含量,且与麻醉深度有相同的变化趋势,提示脑区NOS可能是七氟烷的作用位点之一,七氟烷可能通过抑制NOS活性和降低NO含量而发挥麻醉效应。     

一氧化氮/一氧化氮合酶系统在脊髓继发性损伤中的作用

脊髓损伤(spinal cord injury,SCI)是临床亟待解决的一大难题,虽然SCI的实验性治疗在18世纪就已经开始,但迄今尚未取得有意义的突破。原因可能是对SCI后病理发展过程认识不足。目前认为急性脊髓损伤有两种损伤机制,即原发性机械损伤及迟发性结构损害所致的继发性损伤,后者产生的损伤程度更严重、范围更广。因此,虽然原发的脊髓横断伤较少,但由于继发的不可逆的结构的改变,损伤仍然非常严重,故阻断继发性损伤的发生成了SCI研究的焦点。一氧化氮(Nitric Oxide,NO)/一氧化氮合酶(Nitric Oxide Synthase,NOS)系统是近年来被认为在继发…     

一氧化氮与阻塞性黄疸肾功能障碍关系的实验研究

目的: 研究一氧化氮(N0)与阻塞性黄疸(OJ)肾功能障碍的关系. 方法: 雄性SD大鼠胆总管结扎后随机分成5 d、10 d及15 d三组(B1组、B2组、B3组),同时建立对应的假手术对照组.观察肾功能的变化,同时测定血和肾组织N0水平及一氧化氮合酶(NOS)活性,并用图像分析检测NOS-mRNA于肾脏表达的部位和量的变化. 结果: B1、B2及B3各组的血及肾组织NO含量分别是(43.72±10.61)μm01/L,(0.515±0.082)μmol/g@pro;(34.44±9.63)μmol/L,(0.375±0.096)μmoL/g@pro;(27.34±8.88)μmol/L,(0.251±0.086)μmol/g@pro.血及肾组织NO与内生肌酐清除率(Ccr)、肾皮质血流(RCBF)呈正相关.肾组织iNOSmRNA表达增加,血和肾组织NOS活性降低. 结论: 血和肾组织NO水平下降,是导致OJ时肾功能损伤的原因之一,体内NO水平的持续下降是由于NOS活性降低而非NOS基因表达减少.     

脊髓急性损伤时NO、IL-8、IL-6的表达及意义

目的 :研究脊髓急性损害早期白细胞介素 -8(IL 8) ,白细胞介素 -6(IL 6) ,一氧化氮 (NO)及一氧化氮合酶 (NOS)的变化。方法 :76例脊髓急性损害病人 ,根据Franked分类 ,分完全截瘫 (FrankedA)组 ,不完全截瘫 (FrankedB ,C和D)组 ,以ELISA法 ,硝酸还原酶法分别测IL 8、IL 6、NO、NOS的值 ,以健康体检人员作对照。结果 :IL 8、IL 6的值完全截瘫者和不完全截瘫者都显著升高 (P <0 .0 5 ) ,NO、NOS的值完全截瘫者和不完全截瘫者都显著降低 (P <0 .0 5 )。结论 :脊髓急性损害早期IL 8、IL 6显著升高 ,NO、NOS显著降低 ,脊髓急性损害早期IL 8、IL 6、NO参与了脊髓继发性损害。     

脊髓损伤大鼠脊髓组织的病理形态学观察

目的：研究脊髓损伤（SCI）用高压氧（HBO）处理后脊髓的病理学变化。方法：用SD大鼠复制SCI模型，0．1MPa和0．25MPaHBO处理后，取损伤脊髓作HE染色。结果：正常对照组脊髓结构完整，细胞形态正常，分布均匀，胞膜，胞核正常，组织间隙正常，单纯损伤组示组织出血，疏松水肿，细胞空泡变性，神经纤维溶解，消失；处理后，0．25MPaHBO组及0．25MPaHBO＋激素（L，M）组脊髓恢复最明显，组织水肿，细胞空泡变性减轻，细胞形态恢复，结构排列完整，结论：HBO治疗可明显阻止或减轻脊髓损伤的病理变化，有利于脊髓功能的恢复。     

The correlation between nitric oxide and vascular endothelial growth factor in spinal cord injury

STUDY DESIGN: Prospective, randomized, placebo-controlled, experimental study. OBJECTIVES: The issue of whether nitric oxide (NO) production is beneficial or deleterious on ischemic injuries of the central nervous system still remains doubtful. Vascular endothelial growth factor (VEGF) is known to induce the release of NO from endothelial cells. However, the effect of NO on VEGF synthesis is not clear. We aimed to determine the effects of L-arginine and NG-nitro-L-arginine methyl ester (L-NAME) on VEGF synthesis and free radicals in a rat model of spinal cord ischemia-reperfusion (IR) injury. SETTING: Surgical Research Laboratory of a Medical School. MATERIAL AND METHODS: Twenty-eight Wistar rats were divided into four groups as follows (n=7): Sham, IR injury, L-arginine, and L-NAME. Infrarenal abdominal aorta was occluded to induce spinal cord ischemia. L-Arginine (100 mg/kg) and L-NAME (10 mg/kg) were given before aortic occlusion. Biochemical assays of malondialdehyde (MDA), NO and VEGF were carried out in spinal cord specimens. RESULTS: L-Arginine treatment significantly increased MDA and NO, but decreased VEGF levels in spinal cord. However, nonselective inhibition of NOS with L-NAME significantly decreased MDA and NO, but increased VEGF levels. Besides, the positive linear correlation between MDA and NO, and negative linear correlations between MDA, NO and VEGF levels have also been demonstrated. CONCLUSION: Nonselective inhibition of NO synthase activity with L-NAME attenuated free radical formation and increased VEGF level when compared with NO precursor L-arginine in a rat model of spinal cord ischemia. We suggest that inhibition of NO synthase, as well as induction of VEGF, may be a therapeutic option in spinal cord IR injury.     

Spinal cord edema preceding syringomyelia associated with Chiari I malformation--case report

A 38-year-old woman with Chiari I malformation presented with spinal cord edema preceding syringomyelia manifesting as a 5-month history of nuchal pain and numbness of the upper extremities. Magnetic resonance imaging showed spinal cord edema, a poorly defined syrinx at the C-2 to T-2 levels, and distorted cerebellar tonsils. Computed tomography revealed cerebrospinal fluid (CSF) density in the center of spinal cord edema, and positron emission tomography revealed no uptake of L-[methyl-11C]methionine, indicating a non-neoplastic lesion. Craniocervical decompression achieved excellent clinical and neuroradiological outcomes. The success of surgical treatment supports the theory that patients with Chiari I malformation have increased transmural flow of CSF, causing spinal cord edema that progresses to syringomyelia. Early treatment of patients with spinal cord edema is indicated to prevent permanent spinal cord injury due to progressive syringomyelia.     

Increased expression of nitric oxide synthase in human lung transplants after nitric oxide inhalation

BACKGROUND: The effects of the ischemia-reperfusion process of organ transplantation on nitric oxide (NO) synthase (NOS) in humans are unknown. The effects of NO inhalation on endogenous NOS expression and activity are controversial. The authors hypothesized that NO inhalation may affect ischemia-reperfusion-induced alterations of the endogenous NOS system. METHODS: The authors performed lung biopsy on patients in a randomized phase II clinical trial of NO inhalation during lung transplantation. After lung implantation, 20 ppm of NO or placebo gas was administered 10 min after the start of reperfusion. Lung tissues were collected from 20 patients (NO, n=9; placebo, n=11) after cold and warm ischemia, 1 hr and 2 hr after reperfusion. The protein levels of NOS isoforms were analyzed by Western blotting and the total NOS activity was measured. RESULTS: The protein levels of inducible NOS did not change significantly in either of the groups. In contrast, during the 2-hr reperfusion period, constitutive NOS (neuronal NOS [nNOS] and endothelial NOS) tended to decrease in the placebo group, but gradually increased in the NO group. After 2 hr of reperfusion, the nNOS protein in the NO group was significantly higher than that in the placebo group (P <0.05). However, the total NOS activity remained at low levels in both groups. CONCLUSIONS: NO inhalation-induced increase of constitutive NOS proteins indicates the interaction between inhaled NO molecules and lung tissues. However, the activity of these newly synthesized NOS proteins remains suppressed during the ischemia-reperfusion period of lung transplantation.     

急性脊髓外伤后脑脊液脂质过氧化物的变化及意义

测定36例急性脊髓外伤患者伤后48h内CSF—LPO的含量,与正常对照组比较,同时对不同损伤程度及不同预后等的患者进行比较。采用医学统计学方法,予显著性t检验。结果显示急性脊髓外伤患者CSF-LPO含量显著高于正常对照组(P<0.001),且与脊髓损伤程度、脊髓水肿范围、脊髓受压、髓内出血以及预后有关。认为CSF—LPO含量增高,提示有脊髓损伤存在,其检测值的差异对早期估计脊髓损伤程度,指导临床治疗,判断预后有一定意义。     

Role of Spinal NO in Antiallodynic Effect of Intrathecal Clonidine in Neuropathic Rats

Background: The role of spinal nitric oxide (NO) in neuropathic pain remains uncertain. Although intrathecal clonidine causes NO release in the spinal cord, the functional role of spinal No in clonidine-produced analgesia has not been examined. The objectives of this study were to assess the role of spinal NO in maintenance of allodynia and to determine the role of spinal NO in the antiallodynic effect of intrathecal clonidine.

Methods: Allodynia was produced in rats by tight ligation of the left L5-L6 spinal nerves. Intrathecal catheters were inserted with tips in the lumbar intrathecal space. Mechanical allodynia was determined by application of von Frey filaments to the left hindpaw. In the first series of experiments, allodynia was assessed before and after intrathecal injection of saline, L-arginine, an NO donor (SNAP), two NO synthase inhibitors (TRIM and NMMA), or an NO scavenger (PTIO). In the second series of experiments, 20 [micro sign]g of clonidine was injected intrathecally 15 min after intrathecal injection of saline, TRIM, NMMA, or PTIO.

Results: Allodynia was not affected significantly by intrathecal injection of L-arginine, SNAP, TRIM, NMMA, or PTIO. The antiallodynic effect produced by intrathecal injection of clonidine was attenuated significantly by pretreatment with TRIM, NMMA, or PTIO.     

脊髓缺血性损伤的MRI与病理演变对照实验研究

目的：研究脊髓缺血性损伤的MRI变化规律及其特征,及相应的病理机制。方法：以家犬为实验模型,采用颈前路手术入路,损伤颈脊髓前动脉,进行肉眼、光镜观察。同时观察MRI异常信号演变过程和特征性表现。结果：脊髓前动脉损伤后出现脊髓水肿、出血,运动神经元变性坏死等病理性变化。MRI异常信号出现在脊髓前动脉损伤节段的前2／3,多表现为一侧受累及或偏向一侧。结论：脊髓缺血性损伤后的脊髓出血、水肿在MRI得到不同程度的反映。MRI能确定脊髓缺血性损伤的部位。     

在大鼠切口疼痛模型中鞘内新斯的明对脊髓NO/cGMP信号转导系统的影响

目的 了解大鼠切口疼痛模型中鞘内（IT）新斯的明（NEO）对脊髓一氧化合酶（NOS）活性、一氧化氮（NO）产量和环鸟苷酸（cGMP）含量的影响。方法 雄性64只,随机分为四组,每组16只：假手术组（组I0、术前30minIT0．9％氯化钠20μl组（组Ⅱ）、术后30minITNEO10μg组（组Ⅲ）和术前30minITNEO10μg组（组Ⅳ）。按Brennan法制成切口疼痛模型,以累积疼痛评分确定疼痛行为。在术后2h断头取腰段脊髓,以分光光度法测定NOS活性、NO产量;放射免疫法测定cGMP含量／结果 组Ⅲ和组Ⅳ大鼠的累积评分均明显低于组Ⅱ（P＜0．01）。组Ⅱ的脊髓NOS活性、NO产量和cGMP含量均较组Ⅰ明显升高（P＜0．01）。组Ⅳ的脊髓NOS活性、NO产量和cGMP含量均较组Ⅰ明显升高（P＜0．01）。组Ⅳ的脊髓NOS活性、NO产量和cGMP含量均较组Ⅱ明显降低（P＜0．05或0．01）。而两用药组上述指标比较以及用药组与组I比较均无明显差别（P＞0．05）。结论 在大鼠切口疼痛模型中,术前IT NEO的抗伤害作用可能与NO／cGMP信号转导系统有关。