急性脑血管病患者血清一氧化氮和一氧化氮合酶变化规律及临床意义

1980年Furchgott等首先在哺乳动物血管层发现一氧化氮（NO），1992年NO被美国科学杂志评为“年度分子”。一氧化氮合酶（nitric oxide synthease，NOS）分结构型（cNOS）和诱生型（iNOS）。NO与脑血管疾病的关系是近几年国内外研究热点，但关于临床急性缺血性和出血性脑血管病NO及NOS浓度变化规律，以及NO与急性缺血性和出血性脑血管病诊断的相关性研究罕见报道。我们旨在通过观察急性脑血管病患者血清NO、iNOS、cNOS浓度变化，探讨NO浓度对于鉴别诊断急性脑血管疾病的临床意义。     

人工合成E-选择素对大鼠局灶性脑缺血再灌注损伤后脑组织一氧化氮合酶表达的影响

目的 探讨人工合成E-选择素对大鼠局灶性脑缺血/再灌注（I/R）损伤后脑组织一氧化氮合酶（NOS）及血清一氧化氮（NO）含量的影响.方法 采用改良的Zea Longa法建立脑I/R损伤模型.66只雄性SD大鼠随机分为对照组、模型组和人工合成E-选择素治疗组（治疗组）.治疗组大鼠采用股静脉注射人工合成E-选择素10 mg·kg-1.应用硝酸盐还原法测定血清中NO含量和免疫组化法检测缺血区脑组织神经型一氧化氮合酶（nNOS）、诱导型一氧化氮合酶（iNOS）阳性细胞数.结果 ①NO：以对照组NO含量为正常生理数据,模型组脑缺血2h/再灌注2～24h NO含量呈上升趋势,24 h时达高峰,72 h有所降低但仍高于对照组,各时间点与对照组比较明显增高（P＜0.01）;治疗组NO变化趋势同模型组,NO含量较模型组减少（P＜0.05）,较对照组增多（P＜0.01）.②NOS：以对照组nNOS、iNOS阳性细胞数为正常生理数据,模型组nNOS阳性细胞在脑缺血2h/再灌注2h后开始表达,12h达高峰,至24h开始降低,各时间点与对照组比较明显增高（P＜0.01）;模型组iNOS阳性细胞在脑缺血2h/再灌注2h开始出现,并持续增多,随时间延长呈上升趋势,24h达高峰,至72 h出现下降,各时间点与对照组比较明显增多（P＜0.01）;治疗组各时间点nNOS、iNOS阳性细胞变化趋势同模型组,但较模型组减少（P＜0.05）,较对照组增多（P＜0.01）.结论 大鼠脑I/R损伤后脑组织NOS活性表达增多,NO浓度升高导致脑组织损伤;人工合成E-选择素通过降低NOS表达,减少NO释放、减轻炎症反应和脑I/R损伤,起脑保护作用.     

氯美噻唑对大鼠脑出血周边组织一氧化氮含量、一氧化氮合酶活性及细胞凋亡的干预作用

目的 研究氯美噻唑对大鼠脑出血周边组织一氧化氮(NO)含量、一氧化氮合酶(NOS)活性及细胞凋亡的影响.方法 Wistar大鼠112只,随机分为脑出血组和脑出血+氯美噻唑(CMZ)组,两组各分为(出血前和出血后4h、6h、12h、24h、72h、7d)7个时间点.利用化学方法测定大鼠脑出血周边组织NO含量、NOS活性;利用原位末端标记法测定出血周边组织中神经细胞的凋亡情况.结果 大鼠脑出血周边组织NO含量、诱导型一氧化氮合酶(iNOS)、一氧化氮合酶(NOS)4h开始升高(P<0.05),24h到7d显著升高(P<0.01),大约72h左右NO、iNOS、NOS达峰值.大鼠脑出血周边组织6h出现凋亡细胞,12h上升显著(P<0.01),3d凋亡细胞达峰值,与NO、iNOS、NOS峰值对应,7d时仍存在较多凋亡细胞.氯美噻唑干预后,NO含量、iNOS和NOS活性及凋亡细胞数量与脑出血组对应时间点比较显著下降(P<0.01).结论 大鼠脑出血周边组织NO含量增高,iNOS、NOS活性增强,脑出血周边组织神经细胞存在长时间凋亡,NO、iNOS可以促进其凋亡;氯美噻唑干预后NO含量降低,iNOS、NOS活性下降,减少大鼠脑出血周边组织神经细胞凋亡.     

惊恐障碍与心绞痛患者血清一氧化氮水平对照研究

目的:探讨惊恐障碍与心绞痛之间的关系.方法:检测并比较17例惊恐障碍(惊恐障碍组)与27例心绞痛(心绞痛组)及39名健康者(对照组)血清一氧化氮(NO)和一氧化氮合酶(NOS).结果:两患者组血清NO水平均显著低于对照组,惊恐障碍组与心绞痛组比较血清NO水平无显著差异;惊恐障碍组血清NOS水平与对照组比较无显著差异,心绞痛组血清NOS水平显著低于对照组,两患者组血清NOS水平无显著差异.结论:惊恐障碍与心绞痛症状相似可能与NO的下降有关.惊恐障碍成为心绞痛的危险因素由NO下降得到解释.     

癫癎患者血清一氧化氮和一氧化氮合酶活性水平的研究

目的　探讨一氧化氮 (NK)和一氧化氮合酶 (NOS)在癫患者中血清活性水平及意义。方法　采用化学比色法对 10 0例癫患者血清中NO和NOS活性水平进行检测。结果　癫患者间歇期血清中NO和NOS活性水平显著高于对照组 (P <0 0 1)。结论　NO和NOS在癫病理过程中起重要作用。     

氟哌啶醇对雄性大鼠阴茎勃起功能和一氧化氮合酶基因表达及其活性的影响

目的探讨氟哌啶醇对雄性大鼠阴茎勃起功能和一氧化氮合酶（NOS）基因表达及其活性的影响。方法将40只3月龄雄性Sprague-Dawley大鼠随机均分为氟哌啶醇组（20只）和蒸馏水对照组（20只，以下简称对照组）。对两组鼠均每日连续灌胃给药，氟哌啶醇组鼠为氟哌啶醇2mg／kg体质量，对照组鼠为与氟哌啶醇组同等容积的蒸馏水。分别在给药第3，6周时每组各随机取10只大鼠与发情期雌鼠进行交配实验，并判断阴茎勃起功能。以逆转录-聚合酶链反应法测定雄鼠阴茎海绵体组织神经型（nNOS）、内皮型（eNOS）、诱导型（iNOS）NOS的mRNA表达情况，并以NOS活性试剂盒测定总NOS活性（tNOS）以及结构型NOS（cNOS，包括nNOS、eNOS）和iNOS的活性。结果氟哌啶醇组鼠给药第3，6周时雄鼠骑跨次数（U均=6．5，P均〈0．001）、阴茎插入次数（第3周：U=8．0，P=0．001；第6周：U=10．0，P=0．02）低于对照组鼠，差异有统计学意义；两者比率（插入命中率）在给药第6周时亦低于对照组鼠，差异有统计学意义（U=19，P=0，019）。给药第3周时氟哌啶醇组鼠阴茎海绵体组织eNOS mRNA表达低于对照组鼠，差异有统计学意义（t=-3，379，P=0，003）；给药第6周时eNOS及nNOS mRNA表达均低于对照组鼠，差异有统计学意义（eNOS：t=-3．846，P=0，001；nNOS：t=-5，773，P〈0．001）；iNOS mRNA表达在给药第3，6周均未见有明显影响。氟哌啶醇组鼠给药第3，6周阴茎海绵体组织tNOS、cNOS活性低于对照组鼠，差异有统计学意义（t=-2，173 - -4，184；P=0，001—0，048），iNOS活性的差异无统计学意义。结论结构型NOS基因表达以及NOS活性降低，可能是氟哌啶醇长期应用后阴茎勃起障碍的发生机制之一。     

儿童癫癎患者血清一氧化氮及一氧化氮合酶活性水平的研究

目的　探讨一氧化氮 (NO)及一氧化氮合酶 (NOS)在儿童癫患者中血清活性水平及意义。方法　采用化学比色法对12 4例儿童癫患者血清中NO及NOS活性水平进行检测。结果　儿童癫患者发作期及间歇期血清中NO及NOS活性水平均显著高于对照组 (P <0 0 1) ,发作期血清中NO及NOS活性水平均高于间歇期 (P <0 0 5 )。结论　NO及NOS在儿童癫病理过程中起重要作用     

一氧化氮合酶抑制剂对脊髓损伤后运动功能的影响

目的观察诱导型和神经型一氧化氮合酶(iNOS,nNOS)抑制剂对大鼠脊髓损伤(SCI)后运动功能的影响和机理。方法大鼠脊髓压迫伤后分别给予iNOS和nNOS抑制剂—氨基胍(AG)和7-硝基吲唑(7-NI)进行治疗,24h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,72h后用流式细胞仪检测神经细胞凋亡情况,4周后用电生理和动物行为学等指标评价运动功能的恢复情况。结果AG和7-NI均可以抑制组织中的NO含量,并使NOS活性下降,同时降低神经细胞的凋亡比率,对运动功能的恢复前者优于后者。结论脊髓损伤后应用NOS抑制剂可以使伤后运动功能得到改善,AG的作用似乎更明显,提示iNOS活性变化可能对脊髓损伤的恢复更具决定作用。     

一氧化氮与癫癎的研究进展

癫癎是严重危害人类健康的常见病、多发病,引起癫(?)的病理机制复杂。目前一氧化氮(NO)参与癫(?)的发作已得到公认,但具体机制不明,现就NO与癫(?)的最新研究进展综述如下。1 NO的生物学特性 NO是L精氨酸(L-Arg)在一氧化氮合酶(NOS)作用下生成的,NOS主要有三种类型:Ⅰ型神经元型NOS(nNOS);Ⅱ型诱导型NOS(iNOS);Ⅲ型内皮型NOS(eNOS),nNOS和eNOS属于结构型NOS(cNOS),依赖ca2 或钙调蛋白,快速短暂生成NO。研究     

一氧化氮与Alzheimer病(综述)

目的 概述了在Alzheimer病（AD）脑内一氧化氮（NO）可能介导胶质细胞激活后对神经元的损伤，参与炎性变化的毒性机制。诱导型一氧化氮合酶（iNOS）在AD脑的胶质细胞和微血管内高表达，同时又在神经元内出现。而反应性胶质细胞内既有iNOS的激活又有神经元型NOS（nNOS）激活，共同产生过量的、具有神经毒性的NO。     

Role of nitric oxide in the brain during lipopolysaccharide-evoked systemic inflammation

Although the inducible isoform of nitric oxide synthase (iNOS) is a well-established source of nitric oxide (NO*) during inflammation of the central nervous system (CNS), little is known about the involvement of constitutive isoforms of NOS (cNOS) in the inflammatory process. The aim of this study was to compare the responses of the expression and activity of iNOS and the two cNOS isoforms, neuronal and endothelial (nNOS and eNOS, respectively), in the brain to systemic inflammation and their roles in the cascade of events leading to degeneration and apoptosis. A systemic inflammatory response in C57BL/6 mice was induced by intraperitoneal injection of lipopolysaccharide [LPS; 1 mg/kg body weight (b.w.)]. The relative roles of the NOS isoforms were evaluated after injection of NG-nitro-L-arginine (NNLA; 30 mg/kg b.w.), which preferentially inhibits cNOS, or 1400W (5 mg/kg b.w.), an inhibitor of iNOS. Biochemical and morphological alterations were analyzed up to 48 hr after administration of LPS. Systemic LPS administration evoked significant ultrastructural alterations in brain capillary vessels, neuropils, and intracellular organelles of neurons, astrocytes, and microglia. Apoptotic/autophagic processes occurred in many neurons of the substantia nigra (SN), which coincided with exclusive enhancement of iNOS expression and activity in this brain region. Moreover, inhibitors of both iNOS and cNOS prevented LPS-evoked release of apoptosis-inducing factor (AIF) from SN mitochondria. Collectively, the results indicate that synthesis of NO* by both the inducible and constitutive NOS isoforms contribute to the activation of apoptotic pathways in the brain during systemic inflammation.     

Nitric Oxide Synthase Inhibition Delays Axonal Degeneration and Promotes the Survival of Axotomized Retinal Ganglion Cells

Nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been implicated in neuronal cytotoxicity following trauma to the central nervous system. The aim of the present study was to examine the role of NO in mediating axotomy-induced retinal ganglion cell (RGC) death. We observed increases in iNOS expression by microglia and Müller cells in the retina after optic nerve transection. This was paralleled by the induced expression of constitutive NOS (cNOS) in RGCs which do not normally express this enzyme. In order to determine if NO is cytotoxic to axotomized RGCs, the nonspecific NOS inhibitors Nomega-nitro-L-arginine (NOLA) or N-nitro-L-arginine methyl ester (L-NAME) were delivered to the vitreous chamber by intraocular injections. Both NOLA and L-NAME significantly enhanced RGC survival at 7, 10, and 14 days postaxotomy. The separate contributions of iNOS and cNOS to RGC degeneration were examined with intraocular injections of the specific iNOS inhibitor L-N(6)-(I-iminoethyl)lysine hydrochloride or the specific cNOS inhibitor L-thiocitrulline. Our results suggest that cNOS plays a greater role in RGC degeneration than iNOS. In addition to enhancing RGC survival, NOS inhibitors delayed the retrograde degeneration of RGC axons after axotomy. We conclude that NO synthesized by retinal iNOS and cNOS plays a major role in RGC death and retrograde axonal degeneration following axotomy.     

急性脑梗死患者血浆神经肽Y与血清一氧化氮合酶水平的变化及其临床意义

目的探讨急性脑梗死(ACI)患者血浆神经肽Y(NPY)、血清一氧化氮合酶(NOS)水平的变化及其临床意义。方法分别用放射免疫法、化学比色法、酶法检测30例ACI患者(ACI组)(发病<48 h和第12 d)及27名正常对照者(NC组)血浆NPY、血清结构型NOS(cNOS)、诱导型NOS(iNOS)及三酰甘油(TG)水平,头颅MRI检查测量脑梗死灶体积,应用美国国立卫生研究院卒中量表(NIHSS)评定神经功能缺损程度。结果与NC组比较,ACI组NPY水平差异无统计学意义;血清cNOS水平发病<48 h显著降低(P<0.01),并与梗死体积、同期NIHSS评分呈负相关(r=-0.368、-0.457,均P<0.05),与NIHSS评分差值呈正相关(r=0.466,P<0.05);血清iNOS水平发病<48 h显著升高(P<0.01),与梗死体积、同期NIHSS评分及两次检测的血TG水平呈正相关(r=0.390、0.362、0.411、0.395,均P<0.05),与NIHSS评分差值呈负相关(r=-0.461,P<0.05)。NPY差值与cNOS差值呈负相关(r=-0.369,P<0.05)。结论 ACI患者发...     

Nitric oxide synthase expression and enzymatic activity in multiple sclerosis

We used post-mortem magnetic resonance imaging (MRI) guidance to obtain paired biopsies from the brains of four patients with clinical definite multiple sclerosis (MS). Samples were analyzed for the immunoreactivity (IR) of the three nitric oxide (NO) synthase isoforms [inducible, neuronal and endothelial nitric oxide synthase (NOS)], and enzymatic NO synthase activity. MRI guided biopsies documented more active plaques than macroscopic examination, and histological examination revealed further lesions. Inducible NOS (iNOS) was the dominant IR isoform, while reactive astrocytes were the dominant iNOS expressing cells in active lesions. NOS IR expressing cells were widely distributed in plaques, in white and gray matter that appeared normal macroscopically, and on MR. Endothelial NOS (eNOS) was highly expressed in intraparenchymal vascular endothelial cells of MS patients. A control group matched for age and sex showed no such changes. Our data support the hypothesis that NO is a pathogenic factor in MS, and that NOS IR is strongly expressed in brain regions appearing normal by MRI.     

Nitric oxide synthase in cerebral ischemia

The results of our continuing studies on the role of nitric oxide (NO) in cellular mechanisms of ischemic brain damage as well as related reports from other laboratories are summarized in this paper. Repetitive ip administration ofN ^G-nitro-L-arginine (L-NNA), a NO synthase (NOS) inhibitor, protected against neuronal necrosis in the gerbil hippocampal CA1 field after transient forebrain ischemia with a bell-shaped response curve, the optimal dose being 3 mg/kg. Repeated ip administration of L-NNA also mitigated rat brain edema or infarction following permanent and transient middle cerebral artery (MCA) occlusion with a U-shaped response. The significantly ameliorative dose-range and optimal dose were 0.01–1 mg/kg and 0.03 mg/kg, respectively. Studies using a NO-sensitive microelectrode revealed that NO concentration in the affected hemisphere was remarkably increased by 15–45 min and subsequently by 1.5–4 h after MCA occlusion. Restoration of blood flow after 2 h-MCA occlusion resulted in enhanced NO production by 1–2 h after reperfusion. Administration of L-NNA (1 mg/kg, ip) diminished the increments in NO production during ischemia and reperfusion, leading to a remarkable reduction in infarct volume. In brain microvessels obtained from the affected hemisphere, Ca²⁺-dependent constitutive NOS (cNOS) was activated significantly at 15 min, and Ca²⁺-independent inducible NOS (iNOS) was activated invariably at 4 h and 24 h after MCA occlusion. Two hour reperfusion following 2 h-MCA occlusion caused more than fivefold increases in cNOS activity with no apparent alterations in iNOS activity. Thus, we report here based on available evidence that there is good reason to think that NOS activation in brain microvessels may play a role in the cellular mechanisms underlying ischemic brain injury.     

神经源型一氧化氮合酶C276T基因多态性与抑郁症相关分析

目的测定抑郁症患者抗抑郁剂治疗前后血浆一氧化氮（NO）水平变化,旨在探讨神经源型一氧化氮合酶（nNOS）基因C276T多态性与血浆NO浓度及抑郁症发病相关性。方法采用硝酸盐还原酶法测定正常对照组及抑郁症患者治疗前后血浆NO水平;全部受试者取全血标本提取基因组DNA,并采用PCR-RFLP方法对nNOS基因C276T多态性进行基因分型。结果患者组疗前血浆NO水平为（76.8±31.6）μmol/L显著高于疗后[（66.9±25.7）μmol/L,P=0.044]及正常对照组[（64.2±33.3）μmol/L,P=0.02],两组疗后血浆NO水平相比差异无显著性（P=0.588）;根据PCR-RFLP结果,nNOS基因可见两种等位基因条带C、T,组成三种基因型CC、CT、TT,两组等位基因及基因型分布频率差异无显著性（均P〉0.05）,且携带不同基因型者之间血浆NO水平差异亦无显著性（均P〉0.05）。结论血浆NO浓度增高可能是抑郁症发病的影响因素;nNOS基因C276T多态性可能不直接影响血浆NO浓度,也不是抑郁症发病的主要基因因素。     

青白散对慢性软组织损伤模型大鼠骨骼肌一氧化氮合酶系统和一氧化氮的影响*☆

背景：对慢性软组织损伤后一氧化氮合酶系统和一氧化氮的研究目前较少。 目的：观察青白散对大鼠慢性软组织损伤模型骨骼肌中一氧化氮合酶系统和一氧化氮的影响。 方法：雄性 SD 大鼠随机分为对照组、模型组、氨基胍组、青白散组。后3组采用机械损伤法制备慢性骨骼肌损伤动物模型,分别予以生理盐水 10 mL/kg,0.10 g/kg氨基胍,0.54 g/kg青白散,1次/d,连续 14 d。于给药后1,2,3周,分别检测大鼠肌组织一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性。 结果与结论：骨骼肌损伤修复过程中,模型组大鼠骨骼肌中一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性较对照组显著增高;而青白散组和氨基胍组大鼠骨骼肌中一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性均较模型组显著降低。说明青白散可能通过阻抑诱导型一氧化氮合酶诱导过量一氧化氮的产生,为慢性软组织损伤的修复创造了有利条件。     

Nitric oxide synthase and NADPH-diaphorase after acute hypobaric hypoxia in the rat caudate putamen

Changes in the production system of nitric oxide (NO), a multifunctional biological messenger known to participate in blood-flow regulation, neuromodulation, and neuroprotection or neurotoxicity, were investigated in the caudate putamen of adult rats submitted to hypobaric hypoxia. Employing immunohistochemistry, Western blotting, enzymatic assay, and NADPH-diaphorase staining, we demonstrate that neuronal nitric oxide synthase (nNOS) expression and constitutive nitric oxide synthase (cNOS) activity were transiently activated by 7 h of exposure to a simulated altitude of 8325 m (27,000 ft). In addition, endothelial nitric oxide synthase (eNOS) immunoreactivity and blood vessel NADPH-diaphorase staining peaked immediately after the hypoxic stimulus, whereas inducible nitric oxide synthase (iNOS) expression and activity remained unaltered. Nitrotyrosine formation, a marker of protein nitration, was evaluated by immunohistochemistry and Western blotting, and was found to increase parallel to nitric oxide synthesis. We conclude that the nitric oxide system undergoes significant transient alterations in the caudate putamen of adult rats submitted to acute hypobaric hypoxia.