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1.
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。  相似文献   

2.
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.  相似文献   

3.
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。  相似文献   

4.
利用SABC免疫组织化学方法,研究神经型一氧化氮合酶(nNOS)阳性神经元在家兔脑干中的分布和衰老变化。结果表明,家兔脑干内分布有丰富的nNOS阳性神经元;阳性神经元主要分布于动眼神经核、红核、脑桥核、三叉神经感觉主核以及脑干的网状结构等;在中央灰质周围、上丘(前丘)浅灰质层、臂旁核、中央上核、舌下神经核、下橄榄核、楔束核等核团也发现一些阳性神经元。对动眼神经核、红核、脑桥核、三叉神经感觉主核和延髓的外侧网状核这5个核团内阳性神经元的数量、胞体平均截面积和最长突起长度在5个年龄组的变化进行了比较。与成年兔相比,仔兔、青年兔阳性神经元的数量、胞体平均截面积和最长突起长度均没有显著性变化(P0.05),但老年兔(36月龄)阳性神经元的数量和最长突起长度都显著减少(P0.05),胞体平均截面积在动眼神经核、脑桥核、三叉神经感觉主核和外侧网状核减小,而在红核则增大(P0.05)。结果提示,脑干内丰富的nNOS阳性神经元,可能通过其生成的NO参与内脏活动、感觉和运动的传导以及睡眠和觉醒等脑的高级整合功能的调节;随着年龄的增长,nNOS阳性神经元的衰老变化会影响NO的合成与释放,从而影响它们在脑干中的正常生理功能。  相似文献   

5.
王昱  秦序  何九军 《中国畜牧兽医》2021,48(10):3864-3871
试验旨在探讨白肉灵芝水提物(Ganoderma leucocontextum aqueous extracts,GLAE)对脑缺血后海马神经元的保护作用及机制。将50只健康大鼠分为对照组、模型组、GLAE低(0.05 mg/(g·BW))、中(0.1 mg/(g·BW))、高(0.2 mg/(g·BW))剂量组。利用双侧颈总动脉夹闭法建立大鼠脑缺血模型,GLAE组灌胃不同剂量的GLAE干预,对照组和模型组灌胃同体积的生理盐水,连续2周。用跳台试验方法检测记忆获得、记忆巩固和记忆再现障碍大鼠的学习记忆能力,HE染色观察大鼠海马组织的病理形态的变化,比色法检测海马组织一氧化氮合酶(nitric oxide synthase,NOS)活性和一氧化氮(nitric oxide,NO)含量,Western blotting和实时荧光定量PCR法分别检测海马组织生长相关蛋白-43(growth associated protein-43,GAP-43)和脑源性神经生长因子(brain derived neurotrophic factor,BDNF)的水平。结果显示,与对照组相比,模型组大鼠跳台试验的逃避潜伏期显著缩短、电击次数显著增加(P<0.05);海马神经元细胞出现明显核固缩、排列松散紊乱等退行性改变,细胞数量显著减少(P<0.05);海马组织NOS活性和NO含量均显著降低(P<0.05);大鼠海马组织GAP-43蛋白表达量显著升高(P<0.05);海马组织BDNF mRNA表达量显著下调(P<0.05)。与模型组相比,GLAE干预后,大鼠逃避潜伏期均显著延长、电击次数均显著减少(P<0.05);GLAE高剂量组大鼠CA1区和齿状回锥体神经元细胞形态明显改善,神经元数量显著增加(P<0.05);GLAE低剂量组对NOS活性影响不明显(P>0.05),显著增加NO含量(P<0.05),GLAE中、高剂量组NOS活性和NO含量均显著升高(P<0.05);GLAE低、中、高剂量组海马组织GAP-43蛋白表达量均显著增加(P<0.05);GLAE低、中、高剂量组海马组织BDNF mRNA表达量均显著增加(P<0.05)。以上结果表明,GLAE可通过提高NOS活性和NO水平、促进海马神经发生和功能恢复对脑缺血后海马神经元损伤有一定的保护作用,从而改善大鼠认知功能,0.2 mg/g GLAE效果最好。  相似文献   

6.
观察赛拉唑对大鼠不同脑区NOS活性、NO和cGMP含量的影响,以探讨NO-NOS-cGMP信号转导系统对赛拉唑全麻分子机理的调控.Wistar纯种大鼠84只,随机选取12只为生理盐水对照组,其余随机均分为低剂量赛拉唑用药组和高剂量赛拉唑用药组,每个剂量组又分为麻醉期、翻正反射恢复期和苏醒期3个亚组(各12只).用分光光度法测定大鼠不同脑区NOS活性和NO产量,放射免疫法测定脑cGMP含量.结果表明,赛拉唑能明显地抑制大鼠大脑皮质、小脑、海马和脑干NOS活性、NO和cGMP含量.并且NOS活性、NO含量的抑制作用呈现荆量依赖性增加趋势,这种变化与大鼠赛拉唑麻醉后行为学变化相吻合.结果提示,NO-NOS-cGMP信号传递系统参与了赛拉唑全麻作用产生的分子学机制的调控.  相似文献   

7.
以2,4-二硝基氯苯(DNCB)致小鼠结肠炎模型为研究对象,探讨了樗白皮活性成分对小鼠血清中NO含量和NOS活性的影响。小鼠分成4组(即对照组、预防组、治疗组、模型组)。模型组用DNCB-丙酮-橄榄油制剂先腹部涂抹致敏再进行DNCB-乙醇溶液灌肠;预防组和治疗组分别在制模前、后进行药物灌胃;对照组以乙醇灌肠和生理盐水灌胃。利用比色法对各组动物血清NO含量和NOS活性进行测定。结果,预防组与治疗组NO含量较模型组和对照组显著降低(p<0.001,p<0.01),预防组与治疗组间无差异显著性;预防组、治疗组NOS活性较模型组显著降低(p<0.01),但与对照组间无差异显著性。结论,樗白皮活性成分对机体NO和NOS具有调节作用,在结肠炎时能促进机体清除NO含量和下调NOS的活性,对于药物所致的小鼠结肠炎有缓解作用。  相似文献   

8.
噻环乙胺对大鼠不同脑区NOS活性及NO产量和cGMP含量的影响   总被引:5,自引:3,他引:2  
动态观察噻环乙胺对大鼠不同脑区NOS活性、NO产量、cGMP含量的影响,以探讨NO/cGMP信号转导系统对噻环乙胺全麻分子机理的调控。SD大鼠168只,随机分为对照组和高、低剂量组(腹腔注射60、30mg/kg噻环乙胺),每个剂量组又分为麻醉组、恢复Ⅰ组和恢复Ⅱ组3个亚组。用分光光度法测定脑NOS活性和NO产量,放射免疫法测定脑cGMP含量。在两个剂量的麻醉组,不但大脑皮层、海马和丘脑的NOS活性受到明显抑制,而且显著减少上述脑区NO产量和cGMP含量(与对照组相比,P〈0.05)。在高、低剂量的恢复Ⅰ组上述3个脑区的NOS活性、NO产量、cGMP含量均有不同程度的恢复,在恢复Ⅱ组除丘脑cGMP含量明显低于对照组(P〈0.05)外,其余指标均显著恢复(与对照组相比,P〉0.05)。两个剂量组脑干、小脑的NOS活性、NO产量和cGMP含量均无明显的改变。噻环乙胺的麻醉作用可能与抑制大脑皮层、海马和丘脑等脑区NO/cGMP信号转导系统相关。  相似文献   

9.
将20只山羊随机分成5组,分别为对照期组、诱导期组、镇静期组、恢复Ⅰ期组和恢复Ⅱ期组,连续观察镇静状态下山羊的行为学变化,采取不同镇静时期山羊脑组织,测定山羊大脑、海马、丘脑、小脑和脑干内一氧化氮合成酶(NOS)活性、一氧化氮(NO)和环鸟苷酸(cGMP)浓度。结果显示,NOS活性和NO、cGMP含量在镇静期明显下降,恢复期恢复至正常水平,上述指标的变化趋势与山羊行为学变化基本一致。结果表明,咪达唑仑的作用与抑制山羊各个脑区内NO/cGMP信号转导系统有关。  相似文献   

10.
为了研究家兔脑缺血再灌注损伤后边缘系统一氧化氮合酶(NOS)活性的变化及血塞通对其活性变化的影响,探讨血塞通对全脑缺血家兔的脑保护作用.选取3月龄哈白兔63只,体质量(1500±150)g,随机分为脑缺血治疗组,脑缺血未治疗组和对照组3组,手术建立家兔全脑缺血模型,应用生化检测技术测定脑缺血再灌注后不同时间边缘系统NOS活性变化及血塞通对其活性的影响.结果表明,边缘系统内NOS活性在脑缺血再灌注2 h后开始升高,6 h达到高峰,随后逐渐下降,24~96 h活性持续下降,120 h后恢复至正常水平;脑缺血治疗组下降幅度大、速度快,在96 h即恢复至正常水平.缺血治疗组和正常对照组NOS的活性极最著低于缺血未治疗组(P<0.01).结果提示,血塞通可以通过减弱NOS活性进而维持NO的生理含量,对全脑缺血再灌注损伤家兔有明显的脑保护作用.  相似文献   

11.
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.  相似文献   

12.
13.
The present study was planned to evaluate a role of nitric oxide (NO) in the regulation of regular ruminal contractions in conscious sheep. Intravenous infusion of S-nitroso-acetyl-DL-penicillamine (SNAP) at doses of 3-30 nmol kg(-1) min(-1)for 30 minutes inhibited both the amplitude and frequency of ruminal contractions in a dose-dependent manner. However, intravenous infusion of Nomega-nitro-L-arginine-methyl ester (L-NAME) at doses of 0.3-3.0 micromol kg(-1) min(-1)did not alter the basal tone of intraruminal pressure and the amplitude of ruminal contractions. The frequency of contractions was slightly inhibited by L-NAME infusion at 1.0 micromol kg(-1)min(-1). The effects of L-NAME were abolished by simultaneous infusion of L -arginine at 30 micromol kg(-1) min(-1). These results suggest that exogenous NO can diminish the ruminal contractions, while endogenous NO is not involved in the regulatory mechanism of basal tone and regular phasic contractions of the rumen in healthy sheep.  相似文献   

14.
15.
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.  相似文献   

16.
Inflammation is a process consisting of a complex of cytological and chemical reactions which occur in and around affected blood vessels and adjacent tissues in response to an injury caused by a physical, chemical or biological insult. Much work has been performed in the past several years investigating inducible nitric oxide synthase (NOS, EC 1.14.13.39) and nitric oxide in inflammation. This has resulted in a rapid increase in knowledge about iNOS and nitric oxide. Nitric oxide formation from inducible NOS is regulated by numerous inflammatory mediators, often with contradictory effects, depending upon the type and duration of the inflammatory insult. Equine medicine appears to have benefited the most from the increased interest in this small, inflammatory mediator. Most of the information on nitric oxide in traditional veterinary species has been produced using models or naturally occurring inflammatory diseases of this species.  相似文献   

17.
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.  相似文献   

18.
一氧化氮 (NO)是一种最新发现的、哺乳动物中最小、最轻并具有独特理化性质和生物学活性的信息和效应分子 ,能激活靶细胞中的鸟苷酸环化酶 (GC) ,提高环一磷酸鸟苷(cGMP)浓度 ,发挥一系列生物学作用 ,现已成为研究热点之一。NO广泛存在于神经系统、心血管系统、免疫系统、消化系统、生殖系统与呼吸系统等的细胞内 ,是传递神经信息、调节血压以及机构防御等一系列生命活动必不可少的生物信使。因此 ,内源性NO的生物学研究、NO在动物模型大鼠体内的分布及其功能的确定 ,将有助于在动物医学和人类临床医学领域进一步阐明机体某些…  相似文献   

19.
Nitric oxide (NO) is produced by three NO synthases (NOS), iNOS, eNOS, and nNOS. Production of NO by iNOS plays key roles in neurodegeneration, while eNOS is a protective enzyme. This study investigated the neuroprotective effect of melatonin and the levels of NOS isoforms induced by melatonin in ischemic brain injury. Adult male rats were treated with melatonin (5 mg/kg) or vehicle prior to middle cerebral artery occlusion (MCAO). Brain samples were collected at 24 hr after the onset of occlusion. Results confirmed that melatonin significantly reduces infarct area. Western blot analysis was used to evaluate the expression levels of iNOS, eNOS, and nNOS. The level of iNOS and nNOS increased in vehicle-treated animals, while melatonin prevented injury-induced increase of iNOS. In contrast to iNOS levels, eNOS levels decreased in vehicle-treated animals, while melatonin prevented the injury-induced decrease of eNOS. This study provides further evidence that melatonin exerts neuroprotective effects, and the regulation of NOS isoforms by melatonin may contribute to the neuroprotective effects.  相似文献   

20.
Expression of nitric oxide synthase isoforms in the testes of pigs   总被引:1,自引:0,他引:1  
This study examined the expression of three isoforms of nitric oxide synthase (NOS) in the testes of pigs. Immunohistochemical studies demonstrated the presence of nNOS, eNOS and iNOS in interstitial cells, primary spermatocytes and spermatids. Positive immunoreactions for eNOS and iNOS were detected in peritubular myoid cells. Some vascular endothelial cells were positive for nNOS and eNOS. The expression of nitrotyrosine was detected in interstitial cells. In addition, the histochemical study revealed that all the interstitial cells were stained positively for NADPH-diaphorase, although some spermatids and vascular endothelial cells displayed moderate enzymatic activity. These findings suggest that three isoforms of NOS are expressed in the testis of pig and that they play important roles in the biology of interstitial cells that produce testosterone, as well as in spermatogenesis in the seminiferous tubules.  相似文献   

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