大鼠小肠移植术后血清一氧化氮及小肠组织一氧化氮合酶和诱导型一氧化氮合酶活性的变化

目的：研究同种大鼠小肠移植后内源性一氧化氮、一氧化氮合酶(nitric oxide synthase，NOS)及诱导型一氧化氮合酶(inducible nitric oxide synthase，iNOS)的变化及一氧化氮与急性排斥反应的关系。方法：以大鼠小肠移植为研究对象，16只SD大鼠进行同系移植作为对照组．8只SD大鼠和8只Wistar大鼠进行同种移植作为实验组，两组移植后分别于第3，5，7天同时取血液及小肠组织，病理为常规苏木精一伊红染色观察，血清一氧化氮采用硝酸还原酶法测定，NOS和iNOS采用分光光度法测定。结果：在急性排斥反应发生的早期实验组血清一氧化氮水平与对照组比较显著升高(术后第3，5，7天t值分别为9．7900，9．0073，6．3159，P&;lt;0．01)，小肠组织NOS及iNOS活性亦显著高于对照组(NOS术后第3，5，7天t值分别为5．9318，9．1237，3．0457，iNOS术后第3，5，7天t值分别为3．2008，5．4930，4．8170，P&;lt;0．01)。结论：大鼠小肠移植后NOS及iNOS变化与排斥反应相关，血清一氧化氮水平的检测可作为干预移植措施始动的指标之一。     

大鼠小肠移植急性排斥反应中血清白细胞介素2及干扰素γ的变化

目的:分析血清白细胞介素2、干扰素γ的水平在大鼠小肠移植急性排斥反应过程中的意义及其评估价值。方法:实验于2005-11/2006-06在解放军第四军医大学西京医院胃肠外科实验室完成。实验方法:小肠移植模型动物选用封闭群SD和Wistar大鼠42只,按随机数字表法分为3组:①对照组(n=6):SD大鼠仅作腹部开关及左肾切除术。②同基因移植组(n=18):供受体均为SD大鼠。③异基因移植组(n=18):供体为Wistar大鼠,受体为SD大鼠。同基因移植组和异基因移植组分别于术后3,5,7天处死大鼠取移植肠段行病理组织学检查,每次6只;同时取血清应用ELISA法检测血清白细胞介素2、干扰素γ水平,对照组大鼠于术后第3天取血清检测。实验评估:排斥程度评估标准分为轻、中、重3度:①轻度:肠黏膜绒毛数目减少,轻度增粗,变短,少量淋巴细胞和粒细胞浸润,少量凋亡上皮细胞。②中度:肠黏膜绒毛明显变矮增宽,黏膜上皮开始脱落,细胞浸润加重,上皮细胞凋亡数目明显增多。③重度:肠绒毛结构消失,上皮脱落,间质大量炎细胞浸润,肌层结构破坏,血管炎。结果:42只大鼠均进入结果分析,无脱失。①异基因移植组大鼠术后第3,5,7天的病理组织学检测结果分别符合轻、中、重度排斥反应,对照组和同基因移植组无明显排斥征象。②异基因移植组大鼠血清白细胞介素2、干扰素γ的表达水平在术后第3,5,7天均显著高于其他2组(P<0.01),白细胞介素2水平升高以第3天明显,第5天达到高峰,第7天即有所下降;干扰素γ水平升高较为缓慢,第7天明显升高。同基因移植组大鼠血清白细胞介素2、干扰素γ水平也高于对照组,但差异无显著性意义(P>0.05)。结论:白细胞介素2、干扰素γ在大鼠小肠移植急性排斥反应过程中发挥重要作用,血清白细胞介素2、干扰素γ水平监测可作为预测及早期诊断大鼠小肠移植急性排斥反应的重要指标。     

L—精氨酸促进移植血管诱导型一氧化氮合酶活性实验研究

目的：探讨外源性L－精氨酸（L－Arg)对移植血管诱导型一氧化氮合酶活性影响,方法：新西兰大白兔15只随机分成3组,建立双侧颈动脉间置颈外静脉移植动物模型,高剂量组每日喂食L－Arg 250mg/kg,低剂量组每日喂食L－Arg 125mg/kg,对照组不喂食L－Arg,持续2周,观察移植血管术前,术后3周和术后6周血浆一氧化氮（NO）水平,组织匀浆一氧化氮合酶（NOS）活性和诱导型NOS的mRNA表达。结果：（1）血浆NO水平：实验组血浆NO水平显著高于对照组,高剂量组血浆NO水平高于低剂量组。（2）组织匀浆NOS活性：实验组组织匀浆NOS活性显著高于对照组,3组术后6周NOS活性高于术后3周。（3）组织匀浆iNOS mRNA表达：术后3周实验组iNOS mRNA表达,对照组无表达;术后6周3组iNOS mRNA均有表达,实验组iNOS mRNA表达高于对照组,高剂量组高于低剂量组,结论：外源性L－Arg促进移植血管NOS表达,增进NOS活性,提高体内NO浓度。     

大鼠脊髓损伤后诱导型一氧化氮合酶的表达及动态改变

目的:探讨大鼠急性脊髓损伤后不同时段髓内诱导型一氧化氮合酶(iNOS)mRNA动态表达。方法:36只SD大鼠抽签法随机分组,任选一组作为对照。采用Allen法制作急性脊髓损伤模型,在损伤后2,6,12,24,48h等时段,以反转录酶聚合酶链式反应(RT-PCR)分析iNOSmRNA表达。在脊髓损伤后24h,用免疫组化方法分析iNOS在脊髓不同类型神经细胞中的表达与分布,并以比色法测定脊髓损伤后血清NOS及一氧化氮的含量。结果:脊髓损伤后,神经元、星形细胞和小胶质中均可见iNOS表达,以神经元表达为主。脊髓损伤后2h可见iNOS表达0.56±0.02,24h达高峰1.20±0.05,48h开始降低0.70±0.06。血清中NOS及一氧化氮的动态改变与损伤组织iNOSmRNA变化趋势相一致。结论:研究资料提示脊髓损伤后脊髓内iNOS表达增高,过量产生的一氧化氮加重了继发性脊髓损伤。     

大鼠小肠移植排斥反应期移植肠RANTES的表达

背景:同种异体移植排斥反应是影响移植物功能和存活的最大障碍,小肠移植排斥反应的诊断与治疗尤为困难.目的:探讨移植肠RANTES的表达在小肠移植急性排斥反应中的意义,以及他克莫司对它的影响.设计、时间及地点:随机对照动物实验,于2003-09/2005-03在解放军第四五一医院普通外科、解放军第四军医大学附属西京医院胃肠外科实验室、解放军第四军医大学基础部电子显微镜中心为大专院校的实验室完成.材料:选用健康成年雄性SD和Wistar大鼠各72只.以SD大鼠为供者,Wistar大鼠为受者,施行异位小肠移植.方法:实施大鼠异位小肠移植,按照不同品系的组合将移植大鼠分为4组(n=18):非手术对照组,Wistar大鼠作为正常对照,不实施小肠移植;同基因移植组,将Wistar大鼠的小肠移植给同品系的Wistar大鼠;异基因移植未治疗组,将SD大鼠的小肠移植给Wistar大鼠,移植后不给予免疫抑制剂治疗;异基因移植他克莫司治疗组,将SD大鼠的小肠移植给Wistar大鼠,移植后0～7 d肌肉注射他克莫司,1 mg/(kg·d).移植后3,5,7 d每组各处死6只大鼠,切墩移植肠标本进行组织病理学检查,并采用免疫荧光染色和激光扫描共聚焦显微镜技术对移植肠RANTES的表达进行连续定量测定.主要观察指标:①各组大鼠移植肠的组织病理学改变.②不同时间点移植物内RANTES阳性细胞的表达变化.③他克莫司对异基因移植大鼠移植肠RANTES表达的抑制作用.结果:72只受体大鼠均进入结果分析.异基因移植末治疗组大鼠后3,5,7 d移植肠符合轻、中、重度急性排斥反应的病理学诊断标准;他克莫司治疗组大鼠和同基因移植对照组大鼠在观察期内未发现明显排斥反应征象.异基因移植未治疗组大鼠的移植肠RANTES表达在术后均显著高于其他3组(P<0.01),其动态变化与急性排斥反应的进程呈正相关;他克莫司治疗组大鼠移植肠RANTES的表达明显低于未治疗组(P<0.01).结论:RANTES阳性细胞在小肠移植急性排斥反应中发挥了重要作用,动态检测移植肠RANTES的表达变化,可能成为小肠移植急性排斥反应有效的诊断指标之一.     

运动后大鼠小脑诱导型一氧化氮合酶的动态变化

目的:通过动态检测运动后大鼠小脑诱导型一氧化氮合酶(inducibleni-tricoxidesynthase,iNOS)活性,探讨一氧化氮在小脑运动调节中的意义及小脑对运动中枢的调节机制。方法:43只SD大鼠分为5组:对照组,运动力竭即刻组,大负荷运动后6,18,24h组,分别测定小脑iNOS活性。结果:对照组与力竭运动后即刻组及大负荷运动后6h组,18h组和24h组iNOS观测值分别是(1516.939±252.852),(2406.874±342.065),(2249.791±107.140),(1686.835±205.366)和(1600.744±109.029)μkat/g。力竭组小脑iNOS活性明显升高,与对照组相比,差异有显著性意义(t=6.276,P=0.000)。大负荷运动后6h组小脑iNOS活性明显升高,与对照组、大负荷运动后18,24h各组相比,差异有显著性意义(F=28.760,P分别为0.000,0.000,0.000)。结论:大鼠小脑iNOS活性在力竭运动后即刻、大负荷运动后6h明显升高,表明一氧化氮参与了运动调节,是小脑对运动调节的中枢机制之一。     

幼龄成骨细胞移植促进骨质疏松性骨折愈合中不同类型一氧化氮合酶的动态表达

目的:追踪观察移植细胞在骨折愈合不同时间点的神经型一氧化氮合酶、诱导型一氧化氮合酶与内皮型一氧化氮合酶动态表达的生物学意义。方法:实验于1999-01/2004-02在中山大学动物试验中心、中山大学病理教研室完成、中山大学肿瘤防治中心完成。选择SD清洁级大鼠96只,按配对原则分为实验组48只,对照组48只;SD清洁级乳鼠20只进行成骨细胞原代培养。建立SD大鼠老龄骨质疏松骨折的动物模型,实验组将SD乳鼠颅骨体外培养的成骨细胞移植到SD雌性大鼠骨质疏松性骨折部位,对照组注入等量无血清培养液。手术后3,7,10,14,21,28,56,84d处死,每组每个时间点6只。用免疫组化检测骨折愈合不同时相的标本诱导型一氧化氮合酶、内皮型一氧化氮合酶和神经元型一氧化氮合酶的动态表达情况。结果:96只大鼠均进入结果分析。实验组:诱导型一氧化氮合酶在3d左右可见较多阳性表达的细胞,7d有表达高峰。内皮型一氧化氮合酶在3d左右可见少量阳性细胞,14d有表达高峰。神经元型一氧化氮合酶在10d左右可见少量阳性细胞,14～21d表达稍有增高,整个实验过程中神经元型一氧化氮合酶表达较弱,表达高峰不明显。而对照组诱导型一氧化氮合酶、内皮型一氧化氮合酶均有较弱表达,表达峰低平,而神经元型一氧化氮合酶表达很弱,未见明显表达高峰。结论:诱导型一氧化氮合酶、内皮型一氧化氮合酶在成骨细胞移植促进老年骨质疏松性骨折愈合的表达具有时效性,且表达的定位细胞不同,表达的量有差别,提示骨折部位一氧化氮合酶的释放可能对促进骨质疏松性骨折愈合有意义。神经元型一氧化氮合酶在成骨细胞移植促进老年骨质疏松性骨折愈合过程中的作用不明显。     

辛伐他汀对脂多糖诱导肺损伤大鼠的一氧化氮合酶的影响

目的 探讨辛伐他汀对脂多糖(LPS)诱导急性肺损伤大鼠的一氧化氮合酶(NOS)的影响.方法 30只SD大鼠随机分为对照组、LPS组和辛伐他汀治疗组,治疗组又分1 h、3 d和7 d组,每组6只.治疗组大鼠在实验前经胃管分别给予辛伐他汀10 mg/kg(4 ml/kg)治疗1 d,3 d,7 d,每天1次;对照组和LPS组则给予蒸馏水(4 ml/kg),每天1次,连续7 d.在最后一次给药1 h后,LPS组和治疗组大鼠从尾静脉注射LPS 5 mg/kg(2.5 ml/kg),对照组则予注射无菌生理盐水(2.5 ml/kg).观察6 h,处死大鼠,取样,比色法测定血清和肺匀浆诱导型一氧化氮合酶(iNOS)、构成型一氧化氮合酶(cNOS)和一氧化氮(NO)水平,免疫组化法检测肺组织iNOS和内皮型一氧化氮合酶(eNOS)的表达.结果 LPS组血清和肺匀浆NO均高于对照组(p<0.001),治疗组则低于LPS组(P<0.05);LPS组血清和肺匀浆iNOS活力均高于对照组而cNOS活力则降低(P<0.05),治疗组肺匀浆iNOS活力显著低于LPS组而eNOS显著升高(P<0.001);免疫组化显示:LPS组肺组织iNOS表达强于对照组,而eNOS表达则显著减弱,治疗组的iNOS表达弱于LPS组,eNOS表达则显著增强,与其减轻肺损伤相关.结论 辛伐他汀可逆转LPS诱导的肺组织iNOS活性的升高和eNOS活性的下降,减轻内毒素性肺损伤.     

神经营养因子对大鼠学习记忆及海马一氧化氮合酶阳性神经元数目的影响

背景:神经营养因子在神经系统发育和正常生理功能维持及神经损伤中起着重要的作用。对神经营养因子的研究是目前神经科学领域的热点和前沿课题之一。目的:研究脑室内注射脑源性神经营养因子(brain-derivedneurotrophicfactor,BDNF)抗体阻断内源性BDNF对大鼠海马一氧化氮合酶(nitricoxidesynthase,NOS)阳性神经元数目的影响。设计:随机对照的实验研究。地点和对象:实验地点在中山大学基础医学院脑研究室。实验对象为健康雄性SD大鼠13只。干预:大鼠脑室内注射BDNF抗体一周后,采用Morris水迷宫进行行为检测。主要观察指标:观察大鼠定位航行试验和空间探索试验状况,并用NADPH-黄递酶组化染色方法观察海马NOS阳性神经元数目的变化。结果:定位航行试验:实验组大鼠平均逃避潜伏期为(33.46±2.64)s,对照组为(17.71±1.86)s,两者差异具有非常显著性意义(t=4.8733,P<0.01);空间探索试验:实验组大鼠在平台象限游泳距离百分比为(28.89±6.31)%,对照组为(41.99±7.46)%,实验组明显低于对照组(t=3.3907,P<0.01);与对照组相比,实验组大鼠空间学习和记忆能力明显下降。实验组大鼠海马CA1区NOS阳性神经元数目(38.37±5.23)明显少于对照组(49.53±5.74)(t=8.200,P<0.01);实验组DG区NOS阳性神经元数目(48.77±5.51)明显少于     

腺病毒转染一氧化氮合酶基因抑制大鼠静脉桥血管内膜增生

目的探讨转染一氧化氮合酶（NOS）基因对自体移植静脉内膜增生的影响.方法制作20只自体颈静脉腹主动脉移植Wistar大鼠模型,实验组、对照组各10只.移植前,实验组血管行腺病毒介导的eNOS溶液浸泡,对照组仅行空载腺病毒溶液浸泡.术后2周取出移植血管,利用病理学、免疫组织化学、RT-PCR检测移植血管内膜厚度、管腔狭窄度、内膜血管平滑肌细胞（VSMC）数及PCNA阳性表达、血管eNOS mRNA表达情况.结果实验组移植血管内膜厚度、管腔狭窄度、VSMC数及PCNA阳性表达均较对照组明显减小或减少,而eNOS mRNA表达则明显增加（均P＜0.01）.结论移植血管转染NOS基因可有效抑制移植静脉内膜的增生.     

Regulation of nitric oxide synthase]

Nitric oxide (NO) synthase is known to be widely distributed in various cells. We characterized this enzyme using partially purified enzyme fractions from rat neutrophils, macrophages, and cerebellum. The cerebellar fraction required Ca(2+)-calmodulin, while that from macrophages required neither calmodulin nor Ca2+. The neutrophil fraction required Ca2+. The enzyme was inhibited by analogues of the substrate, L-arginine. N omega-nitro-L-arginine (NNA) was 20 times more potent than L-NG-monomethyl-arginine (NMA) in blocking the cerebellar enzyme. In contrast, NNA and NMA were about equipotent against neutrophil and macrophage enzymes. These data suggest that the enzyme is regulated by 3 different mechanisms in these cells, with differences between the cerebellar and neutrophil or macrophage enzyme in the catalytic binding site.     

Exogenous nitric oxide regulates activity and synthesis of vascular endothelial nitric oxide synthase

Background Nitric oxide (NO) – a major signalling molecule of the vascular system – is constitutively produced in endothelial cells (EC) by the endothelial NO synthase (eNOS). Since a reduced NO synthesis is an early sign of endothelial dysfunction and NO delivering drugs are used to substitute the impaired endothelial NO production, we addressed the effect of exogenous NO on eNOS in human umbilical venous endothelial cell cultures. Materials and methods The synthetic NO donor DETA/NO (trade name, but in the following we refer to detNO), that releases NO in a strictly first order reaction with a half life of 20 h, was used in our experiments. Results Short‐term (20–30 min) detNO treatment of EC increases the Ser¹¹⁷⁷ phosphorylation of the constitutively expressed endothelial NOS and the production of endogenous NO generated by eNOS from [³H]arginine. The phosphorylation of eNOS is Akt‐dependent and completely reverted by the phosphatidylinositol‐3 kinase (PI‐3K) inhibitor LY294002. A prolonged continuous exposure of EC to detNO 150 µmol L^?1 over a period of 24–48 h causes a reversible cell cycle arrest at G₁‐phase associated with a larger cell volume and increased cell protein content (hypertrophic phenotype of EC). The eNOS protein and mRNA of the hypertrophic cells and the generation of endogenous NO are reduced but eNOS phosphorylation could still be elevated by stimulation with vascular endothelial growth factor. Conclusions Our data explain clinical studies describing a short‐term but not a long‐term benefit of NO treatment for patients with cardiovascular risk factors. The results could be a rational approach to develop a generation of NO donors accomplishing a retarded release from NO donors that mimic the low continuous pulsatile stress‐induced release of endogenous NO.     

Modulation of nitric oxide synthase by nitric oxide donor compounds in migraine

A controlled study was performed to assess the involvement of the nitric oxide pathway in migraine pathophysiology. Thirteen patients with migraine without aura and seven clinically healthy subjects (C) were selected. All of the migraine patients were studied both before, during an asymptomatic phase (t ₀), and 1 h after the administration of 5 mg isosorbide dinitrate, a nitric oxide donor able to induce an experimental migraine attack (t ₁). The nitric oxide levels were analyzed as nitrite accumulation in serum samples, in peripheral blood mononuclear cell extracts, and culture supernatants. Basal nitrite levels in serum samples and peripheral blood mononuclear cell culture supernatants of migraine patients and healthy subjects indicated that migraine patients possess an activated nitric oxide synthesis pathway (t ₀ vs. C F=8.16,P<0.01 and F=16.2,P<0.01, respectively). As expected, in the migraine patients treated with the nitric oxide donor, a marked increase of nitrite levels was observed in sera (t ₁ vs.t ₀ P<0.05,t=3.05). In contrast, during the nitric oxide donor-induced migraine attacks a statistically significant decrease of nitrite levels in peripheral blood mononuclear cell culture supernatants was observed (t ₁ vs.t ₀ P<0.01,t=−4.03), whereas a significant increase of nitrite in total cell extracts was detected (t ₁ vs.t ₀ P<0.001,t=−6.89). These preliminary data suggest that nitric oxide could be involved in the neurovascular modifications leading to a migraine attack.     

大鼠创伤性脑水肿一氧化氮及其合成酶的变化

目的：探讨脑损伤后一氧化氮（ＮＯ）及一氧化氮合酶（ＮＯＳ）与脑水肿的关系。方法：建立大鼠创伤性脑水肿模型,按不同时间点处死动物,测定其脑含水量及静脉血ＮＯ 和脑组织中ＮＯＳ。结果：脑创伤后脑含水量随静脉血ＮＯ的增加而增加,组织ＮＯＳ则随ＮＯ 的增加而下降。结论：创伤性脑水肿与血ＮＯ 有密切相关性,组织中ＮＯＳ则是该过程的可能催化剂     

Plasma nitric oxide concentrations and nitric oxide synthase gene polymorphisms in coronary artery disease

BACKGROUND: Plasma NOx (nitrate and nitrite) is a stable end product of the vasodilator NO. Several polymorphisms in the endothelial constitutive NO synthase (ecNOS) gene have been reported, including the 4a/4b VNTR polymorphism in intron 4, the E298D mutation in exon 7, and the G10-T polymorphism in intron 23. The aims of this study were to examine plasma NOx in patients with coronary artery disease (CAD) and to assess the association between plasma NOx concentrations and the three ecNOS gene polymorphisms. METHODS: Plasma NOx was measured in samples from 128 healthy controls and from 110 CAD patients at least 2 months after myocardial infarction. Three genetic polymorphisms that are known or have been suggested to be associated with plasma NOx concentration were also analyzed by PCR-restriction fragment length polymorphism. RESULTS: Median plasma NOx was significantly higher (P <0.001) in CAD patients (95.9 micromol/L) than in controls (73.8 micromol/L). Furthermore, the median plasma NOx was significantly higher (P <0.001) in hypertensive CAD patients (116.0 micromol/L) than in controls and normotensive CAD patients (86.0 micromol/L). The G-allele frequency of the G10-T polymorphism in intron 23 was significantly higher in CAD patients than in controls. Other polymorphisms showed no differences in allelic frequencies among the control and CAD groups. In controls, individuals with the E298D mutation in exon 7 (136.1 micromol/L) showed significantly higher (P = 0.001) median plasma NOx than those without this mutation (64.5 micromol/L). CONCLUSIONS: Plasma NOx was higher in hypertensive CAD patients than in normotensive CAD patients and controls. The E298D polymorphism of the ecNOS gene was associated with increased plasma NOx. Further study is needed to understand the gene expression and enzyme activity of ecNOS and their association with genotypes.     

Enhanced nitric oxide concentrations and expression of nitric oxide synthase in acupuncture points/meridians

OBJECTIVES: The objectives of this study were to examine the distributions of nitric oxide (NO) in the skin points (acupoints)/meridian regions and determine whether neuronal nitric oxide synthase (nNOS) protein levels were associated with NO concentrations in the areas. DESIGN: Low skin resistance points (LSRP) on the skin surface in response to electrical stimuli were performed in anesthetized adult rats. The skin together with subcutaneous tissue was isolated in meridian regions from PC 2 to 6, BL 36 to 57, CV 3 to 22, and GV 2 to 14. Control skin tissues were obtained in the areas close to related meridians without containing LSRP. Concentrations of nitrite (NO(2)(-)), nitrate (NO(3)(-)), and total NO(2)(-) plus NO(3)(-) (NO(x)(-)) were quantified in the skin tissues, micropunches of brain nuclei, and blood vessels in a blinded fashion. Western blots were also conducted using polyclonal anti-nNOS and anti-endothelial nitric oxide synthase (eNOS) antibody in the skin tissues. RESULTS: NO(x)(-) and NO(3)(-) concentrations were higher (45 +/- 8% and 43 +/- 7% in the CV, 47 +/- 7% and 51 +/- 9% in the BL, and 47 +/- 8% and 45 +/- 6% in the PC) than those in control regions (p < 0.05, n = 6). NO(x)(-) concentrations are 2- to 3-fold greater in skin tissues than those in brain regions and blood vessels (p < 0.05, n = 6-8). nNOS protein levels were consistently increased in the skin regions of BL, PC, and GV meridians compared with their controls (p < 0.05, n = 5-7) but endothelial NO synthase expression was not changed. CONCLUSION: This is the first evidence showing that NO contents and nNOS expression are consistently higher in the skin acupoints/meridians associated with low electric resistance. The results suggest that enhanced NO in the acupoints/meridians is generated from multiple resources including neuronal NOergic system, and NO might be associated with acupoint/meridian functions including low electric resistance.     

捕食应激对大鼠海马一氧化氮及神经型一氧化氮合酶的影响

目的探讨一氧化氮(NO)在创伤后应激障碍(PTSD)样行为异常大鼠的变化规律,以进一步揭示PTSD的神经生物学机制。方法将144只Wistar大鼠随机分组为捕食应激组(n=72)及正常对照组(n=72),在大鼠捕食应激PTSD动物模型基础上,动态检测大鼠海马、额叶皮层组织匀浆NO、一氧化氮合酶(NOS)含量及神经元型NOS(nNOS)表达。结果应激大鼠海马NO含量于捕食应激后即刻明显高于对照组犤(2.8±0.8)μmol/g,F=23.112,P=0.000犦,12h达高峰(3.9±1.1)μmol/g,与对照组比较,F=56.616,P=0.000;与同组其他时相比较,F=14.917,P<0.05,24h时仍明显增多犤(2.6±0.7)μmol/g,F=23.094,P=0.000犦;海马nNOS表达亦同步增高(应激后即刻,12及24h,F=14.228,21.772,18.500,P<0.01),而海马总NOS活性仅在应激后12h内增高犤应激后即刻及12hNOS分别为(9.8±2.5)mmol/(s·kg),F=32.812,P=0.000及(10.2±2.7)mmol/(s·kg),F=31.395,P=0.000犦。结论严重心理/生理应激所致海马nNOS持续性高表达与NO释放明显增多,在实验大鼠持续性PTSD样行为异常中可能有重要作用。     

不同剂量骨保护素对破骨细胞内一氧化氮生成及内皮型一氧化氮合酶的影响

背景：骨保护素和一氧化氮在防治骨质疏松方面有重要作用,但目前关于两者在抑制破骨细胞增殖分化方面的关系研究较少。
　　目的：验证不同剂量的骨保护素对破骨细胞内生成一氧化氮量及内皮型一氧化氮合酶活性的影响。
　　方法：用抗酒石酸酸性磷酸酶染色验证诱导生成的破骨细胞;将诱导生成的破骨细胞分成6个组,空白对照组不加任何试剂;阴性对照组培养液中加入培养液;骨保护素组分为4组分别加入10,25,50,75μg/L不同剂量的骨保护素试剂。采用Annexinv-FITC细胞凋亡检测试剂盒,利用流式细胞仪测定破骨细胞凋亡率;荧光定量PCR检测破骨细胞标志基因抗酒石酸酸性磷酸酶mRNA及蛋白激酶K mRNA 的表达量变化;一氧化氮检测试剂盒检测破骨细胞中内一氧化氮浓度;内皮型一氧化氮合成酶活力试剂盒检测破骨细胞内一氧化氮合酶的活力;骨保护素各组加入内皮细胞型一氧化氮合酶抑制剂;荧光定量PCR检测破骨细胞特异性酶抗酒石酸酸性磷酸酶 mRNA及蛋白激酶K mRNA表达量的变化。
　　结果与结论：①骨保护素可以抑制破骨细胞的分化生成并诱导其凋亡。②骨保护素的质量浓度与诱导生成的破骨细胞数量及其标志酶mRNA的表达量呈负相关,与破骨细胞凋亡率呈正相关。③骨保护素可以增加破骨细胞内一氧化氮的生成以及内皮型一氧化氮合酶活性的升高;骨保护素的质量浓度与破骨细胞生成的一氧化氮浓度及内皮型一氧化氮合酶活性呈正相关。④Raw264.7细胞在体外培养条件下,骨保护素与一氧化氮在抑制破骨细胞生成及促进其凋亡方面有协同作用,推测两者之间可能存在骨保护素/内皮型一氧化氮合酶/一氧化氮信号通路。