拉莫三嗪及L-硝基精氨酸对颞叶癫痫一氧化氮合酶活性、一氧化氮含量及nNOS阳性神经元形态结构的影响

通过测得家兔颞叶癫痫模型中一氧化氮合酶(NOS)的活性和一氧化氮(NO)的含量,研究L-NNA和拉莫三嗪对其含量变化的影响,探讨NO在颞叶癫痫中的发作机制及这两种药物对脑部神经元的保护作用。选取2.0~2.5kg健康哈白兔60只,随机分为正常对照组、癫痫模型组、拉莫三嗪治疗组和L-NNA治疗组,应用硝酸还原法测定癫痫发作后不同时间脑组织中海马及颞叶NO的含量及NOS的活性。结果显示:发现模型组脑海马及颞叶内NOS的活性从6h开始迅速升高,1d达到峰值,随后逐渐降低,7d后基本恢复正常水平,但仍高于其他各组(P0.05)。L-NNA治疗组和拉莫三嗪治疗组在各时间点极显著或显著低于模型组(P0.01或P0.05),LNNA在6h~1d时对NOS的降低程度显著好于拉莫三嗪组(P0.05)。NO的变化规律与NOS变化规律基本一致且成正相关;利用SABC免疫组化染色检测脑海马内神经性NOS(nNOS)阳性神经元,发现模型组海马内CA3区nNOS阳性神经元密度增加,胞质着色加深,胞体的截面积和突起变小;拉莫三嗪治疗组和L-NNA治疗组的神经元密度有所降低,胞体的截面积和突起长度显著变大(P0.05)。结果显示:NO参与了颞叶癫痫发作的始动过程,高浓度的NO对神经元有损伤作用;L-NNA和新型治疗药拉莫三嗪能明显抑制癫痫发作后NO的浓度,对脑部神经元有一定的保护作用,从而对癫痫发作有较好的治疗作用。     

血塞通及L-硝基精氨酸对脑纹状体出血家兔一氧化氮合酶活性、一氧化氮含量的影响

为了研究家兔脑纹状体出血后一氧化氮合酶(NOS)活性和一氧化氮(NO)含量的变化及L-NNA和血塞通对其变化的影响,探讨NO在脑出血损伤中的作用机制及2种药物对脑神经元的保护作用.选取4月龄健康哈白兔56只,随机分为假手术对照组、模型组,脑纹状体出血血塞通治疗组及脑纹状体出血L-NNA治疗组,手术建立家兔脑出血模型,应用生化检测技术测定各组脑纹状体出血后不同时间出血侧纹状体NOS活性及NO含量.结果表明,模型组脑纹状体内NOS活性6h开始升高,3d达到高峰,随后逐渐下降,9d时基本恢复至正常水平;2治疗组纹状体NOS活性在各时间点极显著或显著低于模型组(P＜0.01或P＜0.05),并且L-NNA在6h～1d时降低脑纹状体NOS活性的程度好于血塞通治疗组(P＜0.05);NO含量的变化与NOS活性的变化基本一致,二者成正相关;利用SABC免疫组织化学法方法检测各组脑纹状体神经型NOS(nNOS)阳性神经元,发现模型组纹状体nNOS阳性神经元密度增加,细胞着色加深,胞体截面积和最长突起长度变小,经过治疗后神经元密度降低,胞体截面积和最长突起长度显著改善(P＜0.05).结果提示:NO参与了脑出血损伤过程,高浓度的NO能发挥神经毒性作用损害脑组织;血塞通和L-NNA通过抑制NOS的活性,降低了脑纹状体NO的含量,对脑出血家兔的脑神经元具有明显的保护作用.     

兔脑NOS阳性神经元的总体分布和形态、结构的研究

为研究一氧化氮合酶（NOS）阳性神经元在各年龄段家兔脑内的分布规律及其衰老性变化，用NADPH-d组织化学技术，观察了一氧化氮合酶阳性神经元在家兔脑内的分布和形态。结果显示：在家兔的小脑、大脑皮质、丘脑下部、中脑、脑桥等处有较多的一氧化氮合酶阳性神经元分布，延髓分布极少。NADPH—d阳性神经元呈蓝色，细胞核不着色，突起染色都很清晰。表明一氧化氮与中枢神经系统的诸多功能有关。     

兔脑nNOS阳性神经元的形态、结构和分布规律

利用SABC免疫组织化学方法，对兔脑神经型一氧化氮合酶（nNOS）阳性神经元的形态、结构及分布规律进行了系统研究，结果表明：①nNOS阳性神经元呈深棕色，着色主要在胞质内，细胞核处较为浅淡；神经元胞体形态多种多样，有三角形、圆形、椭圆形、梭形等，神经元突起有一个或者数个；nNOS阳性神经纤维大多呈棕色串珠样，有些区域的阳性纤维交错分布，相互交织成网状。②家兔的各个脑区均有nNOS阳性神经元和神经纤维出现，其中在大脑皮质、小脑、丘脑下部、中脑和脑桥广泛分布，延髓分布极少。③nNOS阳性神经元，在仔兔时就已基本发育到成年兔水平，以后随着年龄增长逐渐发育成熟至衰老，到2岁龄（老年兔）时就出现了显著的衰老变化，即密度减小，表达强度减弱，第一级突起数减少，最长突起长度变短等。结果提示：nNOS阳性神经元及其催化产生的NO在家兔中枢神经系统的发育和神经调控中起重要作用。     

去卵巢及雌激素替代治疗后家兔海马nNOS阳性神经元的形态结构及分布变化

用SABC免疫组织化学技术,观察家兔海马各区nNOS阳性神经元在去卵巢及雌激素替代治疗后的形态结构及分布变化,为雌激素类药物防治绝经后老年性痴呆症提供理论依据。结果表明,家兔海马各区都有nNOS阳性神经元分布;去卵巢后海马nNOS阳性神经元的形态结构及分布变化有区域差异性:与假手术对照组相比,在海马CA1区、CA3区、齿状回(DG)阳性神经元数量明显减少(P0.05),而在CA2区数量明显增多(P0.05)。CA1、CA3区和DG的阳性神经元胞体截面积明显变小,最长突起长度明显变短,第一级突起数变少,与假手术组有显著差异(P0.05)。CA2区阳性神经元胞体截面积明显变小(P0.05),最长突起长度、第一级突起数增多,但差异不显著(P0.05);nNOS阳性神经元的4种指标在雌激素替代治疗组与假手术组之间无显著差异(P0.05)。结果提示:雌激素可能通过影响海马nNOS的表达来影响脑的学习和记忆功能。     

野菊花提取物对小鼠血清NO、NOS的影响

目的：探讨野菊花提取物对小鼠血清中一氧化氮（NO）、一氧化氮舍酶（NOS）的影响，以研究野菊花对动物心血管系统的药理作用机理。方法：将小鼠随机分为试验组和对照组，试验组小鼠腹腔注射野菊花提取物（2ml／kg），l：K／d，连续7d。用Griess试剂法测定血清中NO的含量；化学比色法测定血清中NOS的含量。结果：试验组小鼠血清中NO、NOS含量均显著高于对照组（P〈0．05）。结论：野菊花提取物通过增强NOS活性而增加NO含量，这可能为其舒张血管内皮、降低血压的作用机理之一。     

兔脑一氧化氮合酶(NOS)阳性神经元的形态、结构和分布

应用MADPH—d酶组织化学技术，对兔脑一氧化氮合酶（NOS）阳性神经元的形态、结构和分布进行了研究。结果显示：①NOS阳性神经元呈蓝色，细胞核不着色，突起染色很清晰；神经元胞体大多呈多角形、梭形，还有一些呈圆形或卵圆形等。②NOS阳性神经元几乎分布于家兔的各个脑区，包括大脑皮质、小脑、丘脑下部、中脑和脑桥。小脑分布最集中，而延髓分布较少。以上结果表明，NOS阳性神经元及其催化产生的一氧化氮（NO）与中枢神经系统的诸多功能有关。     

酮病奶牛血清中NO含量及NOS活性变化的研究

为了深入研究酮病的发生机理,选择荷斯坦奶牛作实验动物,应用酮粉法和改良式水杨醛比色法随机检测分组,Ⅰ组为10头阳性牛、Ⅱ组为10头对照牛。应用硝酸还原酶法测定血清中一氧化氮(NO)含量和一氧化氮合酶(NOS)活性。实验结果表明对照组奶牛血清中的NO含量及NOS活性均显著大于阳性组。由此可知,酮病可导致奶牛血清中NO含量降低、NOS活性下降。     

兔脑nNOS阳性神经元的分布和形态结构

用SABC免疫组织化学技术,观察了神经元型一氧化氮合酶（nNOS）阳性神经元在家兔脑内的分布和形态。结果显示,在家兔的大脑皮质、小脑、中脑、脑桥等处有较多的nNOS免疫阳性神经元分布,延髓分布较为稀少。nNOS免疫阳性神经元呈棕褐色,着色主要位于胞浆内,细胞核着色较淡,nNOS阳性纤维大多呈棕色串珠样。表明一氧化氮作为神经递质,可能与脑的调控功能有关。     

硬枝碱蓬对卡拉库尔羊血清中NO含量及NOS活性的影响

为探讨硬枝碱蓬对卡拉库尔羊血清中一氧化氮(NO)含量及一氧化氮合酶(NOS)活性的影响,选择8只健康卡拉库尔羊,随机分为对照组和试验组,试验组羊日粮添加硬枝碱蓬,分别在试验期第10天、第20天和第30天测定卡拉库尔羊血清NO含量及总一氧化氮合酶(TNOS)和结构型一氧化氮合酶(cNOS)活性.结果表明:硬枝碱蓬对卡拉库尔羊血清中NO含量及TNOS和cNOS活性均有抑制作用,10d时抑制显著,20和30 d时抑制均极显著,且随添加时间的增加抑制作用越来越明显.表明日粮添加适量的硬枝碱蓬可显著提高卡拉库尔羊机体的抗氧化和抗衰老能力,延长其寿命.     

Balb/c小鼠肺组织一氧化氮及一氧化氮合酶的动态变化

为探讨Balb/c小鼠正常生理状况下肺组织中一氧化氮自由基含量以及一氧化氮合酶活性的动态变化,采用电子自旋共振法直接测定了一氧化氮自由基含量,采用分光光度计法测定了一氧化氮合酶的活性.结果表明:在第3,6,7,12天Balb/c小鼠肺组织的一氧化氮自由基含量、一氧化氮合酶活性均无显著性差异(P＞0.05).说明生理状态下,Balb/c小鼠肺组织一氧化氮自由基的产生维持动态平衡.     

Expression of neuronal nitric oxide synthase and renin in dysplastic kidneys of young dogs

Renin and neuronal nitric oxide synthase in the kidney control the renin-angiotensin and tubuloglomerular feedback systems. The present study investigated the expression of renin and neuronal nitric oxide synthase in the dysplastic kidneys of three young dogs. Renin-immunoreactivity, which occurs in the juxtaglomerular and tubular cells of dysplastic kidneys, did not differ from that in the normal kidneys of young dogs. Macula densa cells in the normal kidneys showed neuronal nitric oxide synthase -immunoreactivity, but those in the dysplastic kidneys showed no apparent signals. This observation may be correlated with the pathological mechanisms of renal failure in young dogs.     

Endometrial nitric oxide synthase activity in mares susceptible or resistant to persistent breeding‐induced endometritis and the effect of a specific iNOS inhibitor in vitro

Emerging research suggests that the nitric oxide system may play a role in persistent breeding‐induced endometritis (PBIE) in the mare. Differences in uterine nitric oxide (NO) levels between mares susceptible or resistant to PBIE and a dose‐dependent inhibitory effect of NO on uterine contractility have been demonstrated. The objectives of this study were to investigate the difference in total nitric oxide synthase (NOS) activity of the endometrium between susceptible and resistant mares and the effect of a specific inducible nitric oxide synthase (iNOS) inhibitor on the endometrial NOS activity in vitro. Six susceptible and six resistant mares were selected based on preset criteria and the results of an intrauterine challenge with killed spermatozoa during oestrus. Endometrial biopsy samples were collected 24 hr post‐challenge and cultured at 37°C for 24 hr in L‐arginine supplemented minimum essential medium with or without a specific iNOS inhibitor (1,400 W dihydrochloride, 1 mM). The medium and the cultured endometrial tissue were collected after 24 hr of culture and assayed for NO and total protein, respectively. Total NO content of the medium, normalized to endometrial tissue wet weight or total protein, was used as a measure of endometrial NOS activity. Non‐parametric tests were applied for statistical analysis. Susceptible mares had significantly greater endometrial NOS activity than resistant mares. The iNOS inhibitor treatment significantly reduced NOS activity in endometrial samples derived from susceptible and resistant mares. These findings provide a basis for in vivo testing of specific iNOS inhibitors as preventative or therapeutic options for PBIE in mares.     

Inducible nitric oxide synthase expression in Leishmania-infected dog macrophages

Nitric oxide (NO) production by the inducible NO synthase (iNOS or NOS2) represents one of the main microbicidal mechanisms of murine macrophages, but its role in other animal models is poorly investigated. Therefore, the aim of this work was to evaluate NOS2 expression in dog macrophages infected with Leishmania infantum. Macrophages obtained from peripheral blood of healthy dogs were activated with recombinant human interferon (rhIFN)-γ and bacterial lipopolysaccharide (LPS) and then infected with L. infantum promastigotes, zymodeme MON1. For the immunofluorescence assay fixed macrophages were incubated with polyclonal rabbit anti-NOS2 and then with rhodamine F(ab′)₂ goat anti-rabbit IgG. For immunoblotting, cell lysates were submitted to SDS–PAGE and blots were incubated with polyclonal rabbit anti-NOS2 and then with horseradish peroxidase-conjugated goat anti-rabbit IgG. Results demonstrated that L. infantum-infected cells, after stimulation with rhIFN-γ and LPS, displayed high levels of fluorescence for the NOS2 in their cytoplasm, unlike unstimulated uninfected macrophages. In western blotting, polyclonal anti-NOS2 reacted specifically with a protein band corresponding to 130 kDa. The signal produced in Leishmania-infected cells stimulated with rhIFN-γ and LPS was higher than that produced in Leishmania-infected unstimulated cells. No band was detected in cellular lysates from uninfected unstimulated cells. These results indicate that dog macrophages can express NOS2, and suggest a role for IFN-γ and LPS in NOS2 induction also in this animal model.     

Elevated expression of CAPON and neuronal nitric oxide synthase in the sciatic nerve of rats following constriction injury

Neuronal nitric oxide synthase (nNOS) has been implicated in peripheral nerve lesions and regeneration. The CAPON adaptor protein interacts with the PDZ domain of nNOS, helping to regulate nNOS activity at post-synaptic sites in neurones, but it is not known whether its expression is altered in sciatic nerves after chronic nerve constriction injury. In the present study, the spatiotemporal expression of CAPON was determined in chronically constricted rat sciatic nerves. Similar to the level of protein expression, CAPON mRNA was significantly up-regulated for almost 5 weeks following sciatic nerve injury. Immunohistochemistry demonstrated that increased CAPON was found mainly in S-100-positive Schwann cells. In addition, co-immunoprecipitation demonstrated an interaction between CAPON and nNOS in Schwann cells and the interaction was enhanced in injured sciatic nerves. CAPON may be involved in peripheral nerve regeneration through regulation of nNOS activity.     

Association between intestinal lymphangiectasia and expression of inducible nitric oxide synthase in dogs with lymphoplasmacytic enteritis

Intestinal lymphangiectasia (IL) is a common complication in dogs. Since nitric oxide (NO) is known to relax the lymphatic vessel, we evaluated inducible NO synthase (iNOS) expression using immunohistochemistry in 13 dogs with lymphoplasmacytic enteritis (LPE) with or without IL. The duodenal iNOS expressing cells were significantly increased in dogs with IL-negative or IL-positive LPE dogs (P=0.025, P=0.007) compared with control dogs. However, there was no significant difference in iNOS expression between IL-positive and IL-negative tissues. Based on these results, there is no clear evidence for the NO overproduction in the pathogenesis of IL in dogs with LPE. Factors other than NO could, thus, contribute to IL in dogs with LPE.     

青蒿素与青蒿水提液对感染柔嫩艾美耳球虫肉鸡的疗效评价

为评价青蒿素和青蒿水提液抗球虫的效果,选择体重相近20日龄黄羽肉鸡120只,随机分为健康组,病理组,青蒿组和青蒿素组4组.测定血清中一氧化氮(NO)和一氧化氮合酶(NOS)含量.结果表明,病理组抗球虫指数为52.7,青蒿组为172.6,青蒿素组为145.4;青蒿和青蒿素能够降低血清中NO和NOS含量.说明青蒿水提液和青...     

蕨麻多糖对小鼠淋巴细胞增殖和一氧化氮分泌的影响

为探讨蕨麻多糖（Potentilla anserine polysaccharide，PAP）免疫调节的作用机理，观察了PAP对小鼠脾淋巴细胞体外增殖和分泌一氧化氮的影响。结果显示，50mg／L PAP配合ConA或LPS（lipopolysaccharide，脂多糖）能使小鼠脾淋巴细胞在体外显著增殖（P〈0．05）；100、200及400mg／L PAP配合ConA或LPS可使小鼠脾淋巴细胞在体外极显著增殖（P〈0．01）；与对照组相比，PAP以不同浓度（50～400mg／L）处理小鼠脾淋巴细胞后一氧化氮分泌量均显著升高（P〈0．05）。试验结果表明，蕨麻多糖能明显促进体外培养的小鼠脾淋巴细胞增殖和分泌一氧化氮，与ConA或LPS有协同作用。     

恒河猴脊髓一氧化氮合酶阳性神经元的分布

本文采用NADPH-d酶组织化学的方法，对成年恒河猴脊髓各段内一氧化氮合酶（NOS）活性进行观察。结果显示恒河猴脊髓NOS阳性神经元主要分布在中间部外侧核、中央管周围灰质、后角的Ⅲ和Ⅳ层。前角也有NOS阳性神经元分布。各部位NOS阳性神经元着色深度有所差异。NOS阳性神经纤维主要分布在后角浅层和中间带。恒河猴脊髓阳性神经元及阳性纤维的分布与人类及其它实验动物相似。