一氧化氮合酶与主动脉瘤

一氧化氮合酶(NOS)通过催化L-Arg生成NO参与动脉瘤的变化。本文通过一氧化氮合酶在调节基质金属蛋白酶(MMPs)活性、调节平滑肌细胞凋亡以及动脉壁的氧化损伤中的作用对其与主动脉瘤形成的关系作一综述,若针对一氧化氮合酶在主动脉瘤形成中的关键环节进行干预,有可能为主动脉瘤的治疗提供新的途径。     

雌孕激素与子宫内膜的一氧化氮合酶

NO(NitricOxide) /NOS(NitricOxideSynthase)在雌性生殖生理功能方面如卵泡发育、激素分泌、胚胎着床、维持妊娠、促进分娩及内膜周期性变化、细胞凋亡等方面都具有重要作用。有关子宫内膜NOS的表达及调控机制仍存在异议。三种NOS神经型NOS(neuronalNOS ,nNOS)、内皮型NOS(endothelialNOS ,eNOS)和诱导型NOS(inducibleNOS ,iNOS)在内膜不同部位和时期呈强弱不等的表达 ,生理作用也不尽相同 ,且与雌孕激素对内膜的调节 ,内膜周期性变化关系密切。本文就NOS在子宫内膜的活性表达及其与雌孕激素关系的研究进行综述。     

一氧化氮及一氧化氮合酶在心血管系统中的研究进展

自1987年证实内皮细胞(endo thelial cell,EC)合成并释放一氧化氮(Nitric oxide,NO)以来,NO在心血管系统中的作用即倍受重视。目前的研究表明,一氧化氮及一氧化氮合酶(NO/nitric oxide sgnghase,NOS)不仅在心血管、免疫、神经系统中有着广泛的生理功能,而且参与多种疾病的发生和发展。     

小肠内NOS分布及NO作用研究进展

一氧化氮作为一种细胞间和细胞内的信息物质 ,在小肠的生理病理过程中有重要作用。本文着重介绍小肠内的一氧化氮合酶分布NO与小肠运动、消化吸收、粘膜保护的关系等方面的研究进展。     

一氧化氮及其合酶在大鼠脑内和脑缺血中作用的研究

本文主要介绍了目前国内外对一氧化氮及其合酶在大鼠脑内和脑缺血的作用研究的部分结果,并简要介绍了研究方法。     

一氧化氮及其合酶与卵巢癌关系的研究进展

一氧化氮是一种具有广泛生物活性的小分子化合物,一氧化氮合酶是一氧化氮合成的关键酶.近看来,一氧化氮及一氧化氮合酶在卵巢癌细胞中的产生和表达与肿瘤细胞的增殖、转移和凋亡的关系日益引起人们重视.本文就一氧化氮及其合酶和卵巢癌的作用关系作一综述.     

重组法国梧桐花粉过敏原2( rPla a2) 对诱导型一氧化氮合酶( NOS2)基因启动子活性及基因表达的影响

目的:构建人诱导型一氧化氮合酶(NOS2)基因启动子区,对NOS2 启动子序列进行鉴定并分析其活性;探索重组法国梧桐花粉过敏原2(rPla a2)对人NOS2 基因启动子活性及基因表达的影响。方法:利用PCR 扩增、限制性内切酶双酶切、DNA 连接酶连接、大肠杆菌转化等方法将NOS2 基因启动子区克隆至pGL3-Basic 载体上,将所构建重组报告质粒转染至人胚肾(HEK293T)细胞中,利用双荧光素酶活性分析检测该重组报告质粒启动子活性及检测rPla a2 对人NOS2 基因启动子活性的影响;用实时荧光定量PCR 法检测rPla a2 对人NOS2 基因mRNA 水平的影响。结果:成功构建含有NOS2 启动子的重组报告质粒,与对照(pGL3-Basic) 组相比,含NOS2 启动子区的重组质粒转染组荧光素酶活性显著增高;与不加刺激(NOS2)组相比,加入rPla a2 刺激后含NOS2 启动子区的重组报告质粒转染组荧光素酶活性显著增高,加入rPla a2 刺激后NOS2 mRNA 相对表达水平显著增高。结论:rPla a2 可增强人NOS2 基因启动子活性,并增加其基因表达。     

扬子鳄食管颈段一氧化氮合酶(NOS)阳性神经元及神经纤维的分布

本实验采用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶(NADPH-d)方法,观察扬子鳄食管颈段NOS阳性神经元和神经纤维的分布.结果食管颈段的粘膜下层和肌层分布着较丰富的NOS阳性神经纤维,一些神经纤维交织成丛状,其间散在分布着NOS阳性神经元胞体.粘膜下一些NO S阳性神经丛环绕血管壁走行.     

线粒体一氧化氮合酶的研究进展

Nitric oxide (NO) is an intra - and intercellular messenger with a broad spectrum of activities in the central nervous system, cardiovascular and immune systems. Mitochondrial nitric oxide synthase(mtNOS), which might be a new form of NOS in mitochondria, has been discovered to be active in the regulation of mitochondrial respiration, energy metabolism and manypathophysiological processes. In this review, the location, properties, physiological and pathophysiological significance of mtNOS were summarized.     

实验性精索静脉曲线大鼠睾丸组织和血清一氧化氮和一氧化氮合酶的改变

目的：检测实验性精索静脉曲线大鼠睾丸组织和血清NO含量和NOS活性的改变，以进一步阐明精索静脉曲线的发生机制。方法：通过手术方法建立大鼠精索静脉曲张模型，检测NO和NOS的变化。结果：实验组左侧睾丸组织NO含量显著高于对照组左侧睾丸含量；实验组血清NOS活力明显低于对照组。结论：实验性精索静脉曲张大鼠睾丸组织和血清NO和NOS有改变。     

一氧化氮合酶阳性神经元在肝硬化大鼠中缝核的分布

目的研究肝硬化大鼠中缝核内一氧化氮合酶阳性神经元分布的变化。方法用四氯化碳建立肝硬化动物模型,NADPH-d组织化学方法观察大鼠脑干中缝核内神经元的变化,图像分析仪对神经元的形态及数量进行分析。结果①NOS阳性神经元及纤维广泛分布于脑干中缝核内,特别是中缝背核,且上段多于下段;②肝硬化大鼠NOS阳性神经元脑干中缝核内分布与正常组基本一致,但阳性反应物的密集度明显增高。结论肝硬化后脑干中缝核一氧化氮合酶较正常明显增多,其分布与兴奋性氨基酸分布相互重叠,可以推测它与一些神经递质在脑内共存并激发神经毒作用。     

一氧化氮/诱导型一氧化氮合酶在动脉粥样硬化过程中的作用

 目的：探讨一氧化氮（NO）/诱导型一氧化氮合酶（iNOS）在动脉粥样硬化（atherosclerosis,AS）过程中的动态变化,分析其对动脉粥样硬化形成过程的影响。方法：将60只SD大鼠随机分成2组：对照组及AS组,每组30只。AS组采用维生素D3腹腔注射联合高脂饲料饲养的方法构建动脉粥样硬化模型。用相关生化方法检测血清各项生化指标：总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、空腹血糖和钙离子,比色法检测血清NO浓度,并对主动脉行HE染色,免疫组化技术检测iNOS蛋白表达,将所得数据进行统计分析,用简单线性相关分析NO与钙离子及动脉粥样硬化指数的相关性。结果：90 d后成功构建了主动脉中膜钙化型动脉粥样硬化模型。血清NO浓度在动脉粥样硬化过程中逐步下降,各组间差异均有统计学意义（均P<0.05）。动脉粥样硬化过程中动脉粥样硬化指数与钙离子呈正相关,与NO呈负相关。在90 d的AS组粥样斑块区免疫组化技术检测到iNOS蛋白表达。结论:在动脉粥样硬化形成过程中,主动脉粥样斑块区iNOS蛋白高表达,但血清NO浓度逐渐降低,NO抗动脉粥样硬化作用减弱。     

脑挫伤后一氧化氮合酶阳性细胞及一氧化氮含量的变化

目的　探讨脑挫伤后一氧化氮合酶 (NOS)阳性细胞和一氧化氮 (NO)的变化和意义。方法　采用自由落体法致Wistar大鼠顶叶皮质挫裂伤动物模型。伤后 2 4h、72h和 7d取脑 ,制作冰冻切片 ,采用NADPH组织化学染色 ,显示脑挫伤区NOS阳性细胞。用硝酸还原酶法测定血液和脑组织中NO含量。结果　脑挫伤后 72h ,NOS阳性细胞数密度 (Nv)和面密度(Sv)明显增高 (P <0 0 5 ) ,而且 7d时仍无明显下降。血液和脑中NO含量也增高 ,并与NOS细胞呈平行关系。结论　脑挫伤后不同时间NOS细胞数目和NO含量有明显改变 ,提示NOS和NO参与了脑挫伤的病理过程     

肝硬化大鼠脊髓内一氧化氮合酶阳性神经元分布的研究

目的探讨肝硬化对神经系统所产生的影响及肝硬化大鼠在脊髓中NOS量效关系,即肝硬化大鼠脊髓内一氧化氮合酶分布的研究。方法采用NADPH鄄d组化法及LeicaQ500IW图像分析系统对肝硬化大鼠脊髓颈、胸、腰段一氧化氮合酶阳性细胞进行数量及灰度的测定。结果正常组与肝硬化组分为两个等级:低密区和高密区,低密区灰度定为60,高密区为90,两组Wistar大鼠NOS阳性神经元灰度均为60,差异无显著性。在脊髓灰质区,一氧化氮合酶阳性细胞主要分布在中央管周围即脊髓板层第Ⅹ层和中间外侧核。NADPH鄄d呈色为强阳性,细胞形态多为三角形和梭形,胞核不着色,胞质色深。细胞中等大小,以25μm为主。在脊髓颈、胸、腰各段灰质中间带NOS阳性细胞分布的数量基本相等,没有特异性变化。结论肝硬化大鼠与正常大鼠一氧化氮合酶的表达在脊髓内是相同的。NOS在脊髓节段的分布特性可能说明肝硬化大鼠低级交感神经的调控与正常无异。     

一氧化氮合酶及精氨酸对兔急性胰腺炎的影响

目的:探讨一氧化氮合酶(Nitric Oxide Synthase,NOS)和精氨酸在兔急性胰腺炎中的作用。方法:采用胰管结扎及加压注射法建立兔急性胰腺炎模型;精氨酸组在急性胰腺炎模型制备后经胰管推注精氨酸250mg/kg,采用黄递酶组织化学染色法观察和比较NOS和精氨酸对三组动物胰腺病变的影响。结果:经Winslow法测定动物血清淀粉酶急性胰腺炎组为1318U/L±198.20,精氨酸组为78U/L±13.20,对照组为56U/L±18.60。NOS组化染色显示,急性胰腺炎组胰腺的腺泡细胞被染成深蓝色,精氨酸组胰腺的腺泡细胞被染成蓝色,而对照组胰腺的腺泡细胞被染成浅蓝色,染色强度急性胰腺炎组明显高于对照组。结论:NOS参与急性胰腺炎的病变过程中起重要的介导作用,而精氨酸对急性胰腺炎病变有减轻作用。     

肝硬化大鼠黑质一氧化氮合酶阳性神经元分布的研究

目的　研究肝硬化大鼠黑质一氧化氮合酶 (NOS)阳性神经元及纤维分布的变化。方法　 2 0只Wistar大鼠随机分为肝硬化组与正常组 ,应用NADPH d组化法显示肝硬化大鼠黑质NOS阳性神经元胞体的数量及胞体灰度。结果　肝硬化大鼠黑质一氧化氮合酶阳性神经元数量明显减少但阳性胞体的灰度增加 ,正常组大鼠黑质一氧化氮合酶阳性神经元数量增加但胞体的灰度降低。结论　肝硬化大鼠体内有毒物质使脑细胞广泛受损 ,神经递质传递发生障碍 ,造成肝性脑病的一系列神经系统病症     

Spontaneous recovery of injured Achilles tendon in inducible nitric oxide synthase gene knockout mice

Objective and Design: To determine if inducible nitric oxide synthase (iNOS) gene could affect Achilles tendon healing using iNOS gene knockout mice. Methods: 21 iNOS knockout (iNOS^−/−) mice and 8 of the wild type (iNOS^+/+) mice were utilized in this study. Group 1: iNOS^+/+ mice (n = 8), group 2: iNOS^−/− mice (n = 11) and group 3: iNOS^−/− with a NOS inhibitor, (aminoguanidine, 500 mg/kg/day, via an intraperitoneal mini-osmotic pump for 7 days, n = 10). The right Achilles tendon was transected in all mice and harvested on day 7 for cross-sectional area and biomechanical properties. Serum nitrate concentration of the mice was measured by gas chromatography mass spectrometry (GC/MS). Results: A significant reduction in cross-sectional area of the healing Achilles tendon was observed in group 3 mice compared to group 2 mice (p < 0.01). The serum nitrate concentration in both group 2 and group 3 mice was lower than that in group 1 mice (p < 0.01) iNOS gene deletion and inhibition of NOS did not affect the biomechanical properties of the healing tendons. Conclusions: iNOS gene is not solely responsible for the beneficial effects of nitric oxide (NO) on tendon healing. Received: 30 March 2005; returned for revision 4 August 2005; returned for final revision 27 September 2005; accepted by M. Parnham 28 September 2005     

The nitric oxide pathway is an important modulator of stress-induced fever in rats

Psychological stress evokes a number of physiological responses, including a rise in body temperature (T(b)), which has been suggested to be the result of an elevation in the thermoregulatory set point, i.e., a fever. This response seems to share similar mechanisms with infectious fever. A growing number of studies have provided evidence that nitric oxide (NO) has a modulatory role in infectious fever, but no report exists about the participation of NO in stress fever. Thus, the present study aimed to verify the hypothesis that NO modulates stress fever by using restraint stress as a model. To this end, we tested the effects of the non-specific NO synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) or its inactive enantiomer N(G)-nitro-D-arginine methyl ester (D-NAME) on colonic T(b) of restrained or unrestrained rats. A rapid increase in T(b) was observed when animals were submitted to restraint. Intravenous (i.v.) injection of L-NAME at a dose (10 mg/kg) that caused no change in T(b) when administered alone significantly attenuated the elevation in T(b) elicited by stress, indicating that the NO pathway may mediate stress fever. Moreover, intracerebroventricular (i.c.v.) L-NAME (250 microg/microl) caused a rise in T(b) of euthermic animals and enhanced stress fever, supporting that NO in the central nervous system (CNS) leads to a reduction in T(b) and, therefore, this is unlikely to be the site where NO may mediate stress fever. Taken together, these data indicate that the NO pathway plays an important role in modulating restraint stress-induced fever in rats.     

叶酸对去卵巢大鼠抗氧化酶、一氧化氮合酶和一氧化氮的影响

 目的: 观察叶酸对去卵巢大鼠抗氧化酶、一氧化氮合酶和一氧化氮的影响。方法: 40只3月龄健康雌性SD大鼠,随机分成5组:假手术组、去卵巢组、二乙基己烯雌酚(0.03 mg·kg^-1·d^-1)组、低剂量(5 mg·kg^-1·d^-1)叶酸组和高剂量(20 mg·kg^-1·d^-1)叶酸组。各组大鼠于术后1周开始灌胃给药,假手术组和去卵巢组给予蒸馏水,10周后,取L₅椎体和右股骨行骨密度(BMD)检测;测定血浆和骨匀浆总抗氧化能力(TAC)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)、一氧化氮合酶(NOS)和一氧化氮(NO)水平。结果: 与假手术组比较,去卵巢组大鼠L₅椎体和股骨BMD显著降低(P < 0.01),血浆GSH-Px、NO和骨匀浆TAC、GSH-Px、NOS及NO水平明显降低(P < 0.01),MDA浓度升高显著(P < 0.01);与去卵巢组大鼠比较,高剂量叶酸组大鼠L₅椎体和股骨BMD增加(P < 0.01),骨匀浆TAC、GSH-Px、NOS和NO水平升高(P < 0.01),MDA浓度降低(P < 0.01),血浆GSH-Px和NO水平升高。结论: 去卵巢大鼠体内抗氧化酶、NOS和NO水平降低,氧化应激参与了去卵巢大鼠骨质疏松的发生;高剂量叶酸能提升去卵巢大鼠腰椎和股骨BMD,提高其体内抗氧化酶、NOS和NO水平,改善氧化应激,这可能是高剂量叶酸防治去卵巢大鼠骨质疏松的机制之一。     

Anti-inflammatory effect of Mentha longifolia in lipopolysaccharide-stimulated macrophages: Reduction of nitric oxide production through inhibition of inducible nitric oxide synthase

Abstract

Mentha longifolia is an aromatic plant used in flavoring and preserving foods and as an anti-inflammatory folk medicine remedy. The present study assessed the effects of M. longifolia extracts, including essential oil and crude methanol extract and its fractions (ethyl acetate, butanol and hexane), on nitric oxide (NO) production and inducible NO synthase (iNOS) mRNA expression in lipopolysaccharide (LPS)-stimulated J774A.1 cells using real-time polymerase chain reaction (PCR). The cytotoxic effects of the extracts on the cells were examined and non-cytotoxic concentrations (<0.2?mg/ml) were used to examine their effects on NO production and iNOS mRNA expression. Only the hexane fraction that contained high levels of phenolic and flavonoid compounds at concentrations from 0.05–0.20?mg/ml significantly reduced NO production in LPS-stimulated cells (p?<?0.001). Real-time PCR analysis indicated the ability of this fraction at the same concentrations to significantly decrease iNOS as well as TNFα mRNA expression in the cells (p?<?0.001). All extracts were able to scavenge NO radicals in a concentration-dependent manner. At concentrations greater than 0.2?mg/ml, total radicals were 100% scavenged. In conclusion, M. longifolia possibly reduces NO secretion in macrophages by scavenging NO and inhibiting iNOS mRNA expression, and also decreases TNFα pro-inflammatory cytokine expression, thus showing its usefulness in the inflammatory disease process.