香菇多糖对巨噬细胞一氧化氮和一氧化氮合酶活性的影响

目的研究香菇多糖(LTN)诱导巨噬细胞的一氧化氮(NO)生成和一氧化氮合酶(iNOS)的活性,探讨LTN的免疫调节作用机理.方法采用Griess反应和荧光法测定不同剂量的LTN作用小鼠腹腔巨噬细胞后NO的生成量和iNOS活性.观察mRNA转录抑制剂、蛋白质合成抑制剂和iNOS抑制剂对巨噬细胞NO的生成和iNOS活性的影响.结果LTN能使小鼠腹腔巨噬细胞NO生成增加,iNOS活性增高,并呈作用剂量依赖关系.3种抑制剂均能抑制LTN诱导的小鼠腹腔巨噬细胞N0的生成和iNOS活性.结论LTN能刺激小鼠腹腔巨噬细胞提高iNOS活性和NO的生成.提示LTN的免疫调节作用机制可能与LTN刺激巨噬细胞NO生成有关.     

香菇多糖对巨噬细胞一氧化氦和一氧化氦合酶活性的影响

目的 研究香菇多糖(LTN)诱导巨噬细胞的一氧化氮(NO)生成和一氧化氮合酶(iNOS)的活性，探讨LTN的免疫调节作用机理。方法 采用Griess反应和荧光法测定不同剂量的LTN作用小鼠腹腔巨噬细胞后NO的生成量和iNOS活性。观察mRNA转录抑制剂、蛋白质合成抑制剂和iNOS抑制剂对巨噬细胞NO的生成和iNOS活性的影响。结果 LTN能使小鼠腹腔巨噬细胞NO生成增加，iNOS活性增高，并呈作用剂量依赖关系。3种抑制剂均能抑制LTN诱导的小鼠腹腔巨噬细胞NO的生成和iNOS活性。结论 LTN能刺激小鼠腹腔巨噬细胞提高iNOS活性和NO的生成。提示LTN的免疫调节作用机制可能与LTN刺激巨噬细胞NO生成有关。     

库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮生成的影响

目的研究库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮(NO)生成的影响。方法用G riess法测定巨噬细胞一氧化氮的生成量。结果库拉索芦荟多糖在25～400μg/mL浓度范围可显著促进正常巨噬细胞的NO生成,在50～400μg/mL浓度范围可抑制LPS激活的巨噬细胞的NO生成。结论库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮的生成具有双向调节作用。     

库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮生成的影响

目的研究库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮(NO)生成的影响。方法用G riess法测定巨噬细胞一氧化氮的生成量。结果库拉索芦荟多糖在25~400μg/mL浓度范围可显著促进正常巨噬细胞的NO生成,在50~400μg/mL浓度范围可抑制LPS激活的巨噬细胞的NO生成。结论库拉索芦荟多糖对小鼠腹腔巨噬细胞一氧化氮的生成具有双向调节作用。     

灵芝多糖肽对小鼠腹腔巨噬细胞一氧化氮产生的影响

目的　研究灵芝多糖肽 (GLPP)对小鼠腹腔巨噬细胞一氧化氮产生的影响并探讨其作用机制。方法　以Griess法 ,观察GLPP对LPS诱导小鼠腹腔巨噬细胞一氧化氮(NO)产生的影响 ;以免疫组化法检测诱导型一氧化氮合成酶 (iNOS)的表达 ,观察GLPP对iNOS的影响。结果　GLPP(2 5～ 2 0 0mg·kg-1)灌胃给药 5d或体外给药 (3 12 5～ 2 0 0mg·L-1)均可促进巨噬细胞NO释放 ,但对LPS刺激NO的释放影响不大 ;GLPP(10 0mg·kg-1)灌胃给药 5d或体外给药 (10mg·L-1)均可使巨噬细胞iNOS含量增加。结论　GLPP可增加小鼠腹腔巨噬细胞NO产生 ,其机制可能与其促进巨噬细胞iNOS合成有关。     

锰对仔鼠脑组织一氧化氮合酶活性的影响

为了研究大鼠孕期染锰后 ,其子代脑组织一氧化氮合酶活性的变化 ,对妊娠大鼠腹腔注射氯化锰 ,剂量为 0、7.5、15、30 mg/ kg,然后对其子代 30日龄仔鼠脑组织用组织化学法检测一氧化氮合酶活性 ,并用图象分析仪定量分析。结果表明 :实验各组仔鼠脑组织一氧化氮合酶阳性神经元的截面积、平均吸光度、积分吸光度均明显高于对照组 ( P<0 .0 1)。大鼠孕期染锰 ,使其子代脑组织一氧化氮合酶活性增强 ,促使一氧化氮合成增多 ,从而引起中枢神经受损     

海藻多糖对辐射后巨噬细胞产生一氧化氮的影响

目的:研究海藻多糖(polysaccharides from seaweed,SP)对辐射后巨噬细胞(macrophages,MΦ)产生一氧化氮(Nitric oxide, NO)的影响.方法:用电子自旋共振(electron spin resonance,ESR)技术检测MΦ在8Gy的60Co-γ辐射后NO的波谱积分值,用免疫组化法研究MΦ中诱导性一氧化氮合酶(inducible NO synthase, iNOS)的表达.结果:经60Co-γ辐射后,MΦ产生NO减少,对脂多糖(LPS)、γ-干扰素(IFN-γ)等刺激因子和iNOS抑制剂及NO前体的敏感性降低,且MΦ中iNOS的表达明显下降.SP可部分程度地逆转上述变化.结论:SP可减缓辐射后MΦ产生NO的减少.     

噪声对血清总抗氧化能力和一氧化氮合酶活性影响的调查

目的了解噪声对作业接触工人总抗氧化能力和一氧化氮合酶活性的影响。方法检测接触组和对照组的血清总抗氧化能力（T-AOC）和一氧化氮合酶活性（NOS）。结果噪声组血清T-AOC明显低于对照组组（P〈0.05）、血清总NOS和诱导型NOS活性明显高于对照组（P〈0.05）。结论长期噪声接触可致使机体总抗氧化能力下降和诱导型一氧化氮合酶活性增强。     

戊四唑癫痫大鼠脑组织一氧化氮含量和一氧化氮合酶活性变化

探讨一氧化氮在戊四唑癫病发机制中的作用。方法每天注射戊四唑建立在鼠癫痫模型,测定癫病发作后大鼠大脑皮质,海马一氧化氮和一氧化氮合酶活性变化,结果癫痫发作后海马ＮＯ含量和ＮＯＳ活性显著升高,结 戊四唑诱导的癫痫中具有致痫性。     

花色素苷诱导小鼠巨噬细胞一氧化氮生成及其机制

目的研究花色素苷对小鼠腹腔巨噬细胞一氧化氮(NO)合成的诱导作用及其机制。方法用CCK-8试剂检测花色素苷对小鼠脾细胞增殖的影响;硝酸盐还原酶法检测小鼠腹腔巨噬细胞NO含量;荧光法检测一氧化氮合酶(NOS)活性;RT-PCR检测iNOS mRNA的表达。结果花色素苷可促进小鼠脾细胞增殖,诱导小鼠腹腔巨噬细胞合成NO,提高NOS活性,其中矢车菊素-3-葡萄糖苷能够诱导iNOS mRNA的表达。结论花色素苷能够促进脾细胞的增殖,诱导小鼠腹腔巨噬细胞合成NO,使巨噬细胞激活,具有一定的免疫调节活性。     

骨关节炎患者血清和关节液一氧化氮及其合成酶变化的意义

目的探讨骨关节炎(OA)患者血清及关节液中一氧化氮(NO)和诱生型一氧化氮合成酶(iNOS)与病情程度及活动性的关系.方法对30例轻度(n=7)、中度(n=12)、重度(n=11)骨关节炎患者及24例健康对照者血清及关节液中NO、iNOS、ESR、CRP的含量进行测定.结果中、重度骨关节炎组血清中NO、iNOS水平比健康组升高(P＜0.01);三组骨关节炎关节液中NO、iNOS水平均比对照组明显升高(P＜0.001);重度骨关节炎组血清中NO、iNOS水平与关节液中NO、iNOS水平呈正相关(r=0.589,P＜0.01);重度骨关节炎组关节液中NO、iNOS水平与ESR、CRP呈正相关(r=0.428,p＜0.05).结论iNOS及其产生的NO参与了OA的病变过程,是OA病程发展的重要机制.     

酵母多糖对小鼠腹腔巨噬细胞产生一氧化氮和白细胞介素-1的影响

目的探讨酵母多糖对小鼠腹腔巨噬细胞产生一氧化氮 (NO)和白细胞介素 1(IL 1)的影响。方法将不同剂量的酵母多糖加入体外培养的小鼠腹腔巨噬细胞中 ,取细胞培养上清液根据Griess反应检测NO-2 的量 ,间接反映巨噬细胞产生NO的生成量 ,并用溴化四唑蓝 (MTT)比色法检测上清液中IL 1的生成量。结果酵母多糖可明显促进小鼠腹腔巨细胞产生NO和IL 1,NO的生成量呈现剂量依赖关系。结论酵母多糖可诱导小鼠腹腔巨噬细胞产生NO和IL 1,可能是酵母多糖调节机体免疫功能、杀伤病原微生物和抗肿瘤的重要途径     

罗红霉素通过诱导型一氧化氮合酶/一氧化氮途径抑制哮喘大鼠气道炎症

目的探讨罗红霉素对哮喘大鼠支气管诱导型一氧化氮合酶(iNOS)及一氧化氮(NO)的影响。方法24只成年哮喘大鼠随机分成对照组、哮喘组以及罗红霉素组。对支气管肺泡灌洗液(BALF)细胞总数及嗜酸性粒细胞计数,免疫组织化学检测大鼠支气管上皮细胞iNOS蛋白表达,RT-PCR检测肺组织iNOS mRNA表达,分光光度计检测肺组织iNOS活性及NO含量。双抗体夹心法检测肺组织白细胞介素-4(IL-4)及干扰素-γ(IFN-γ)。结果哮喘组大鼠BALF细胞总数及嗜酸性粒细胞分类分别为(7.28±1.65)×108.L-1、(7.73±1.54)%,均高于对照组(3.76±0.97)×108.L-1、(1.27±0.60)%;罗红霉素组BALF细胞总数及嗜酸性粒细胞分类分别为(5.68±0.95)×108.L-1、(5.54±1.53)%,明显低于哮喘组,差异有统计学意义。哮喘组肺组织IL-4浓度、iNOS活性及NO含量高于对照组,罗红霉素组肺组织IL-4浓度、iNOS活性及NO含量低于哮喘组。哮喘组肺组织IFN-γ浓度低于对照组,罗红霉素组肺组织IFN-γ浓度高于哮喘组。哮喘大鼠支气管上皮细胞iNOS蛋白及肺组织iN-OSmRNA表达分布吸光度值分别为(0.25±0.06)、(0.52±0.14),较对照组[(0.14±0.05),(0.33±0.05)]明显增强;但罗红霉素组iNOS蛋白及mRNA表达为(0.15±0.03)、(0.35±0.07),均明显较哮喘组减弱。结论罗红霉素通过干预哮喘大鼠气道IL-4、IFN-γ以及iNOS/NO体系,抑制哮喘气道炎症反应。     

Role of nitric oxide produced by constitutive and inducible nitric oxide synthases in the mouse gastric fundus

In the present study, the role of nitric oxide (NO) produced by constitutive and inducible nitric oxide synthases (cNOS and iNOS, resepctively) on the contraction and relaxation of fundus in normal and lipopolysaccharide (LPS)-treated mice was examined. A whole fundic ring isolated from mice pretreated with reserpine was mounted in an organ bath containing Krebs' solution with 0.001 mmol/L atropine. Rings were contracted initially by 5-hydroxytryptamine (5-HT; 0.03 mmol/L) before relaxation was induced using ATP (0.03 mmol/L), ADP (0.03 mmol/L), pentoxifylline (0.002 mmol/L), electrical field stimulation (EFS; 50 V, 1 msec, 50 Hz, 3 min) and L-arginine (0.05 mmol/L). All drugs and EFS induced significant relaxation of isolated rings. The relaxations induced were significantly inhibited by N(G)-nitro-L-arginine methyl ester (L-NAME; 1.0 mmol/L). However, the iNOS inhibitors L-N(6)-(1-iminoethyl) lysine hydrochloride (L-NIL; 1.0 mmol/L) and amino guanidine (AMG; 1.0 mmol/L) had no significant effect on tissue relaxation. Then, the relaxant effects of 0.03 mmol/L ATP were tested on precontracted isolated fundic rings taken from 10 mg/kg LPS-treated animals. The non-selective NOS inhibitor L-NAME (10 mg/kg), the iNOS inhibitors L-NIL (3 mg/kg) and AMG (20 mg/kg) and betamethasone (0.1 mg/kg) were used to examine the role of NO produced by iNOS in the relaxation responses. It was found that the level of contraction induced by 0.03 mmol/L 5-HT in rings isolated from LPS-treated animals was significantly (P < 0.5) less than that in rings from untreated mice. However, precontracted tissues from LPS-treated mice were significantly relaxed by ATP and the relaxation response to ATP was significantly inhibited by L-NIL, ANG and betamethasone, but not by L-NAME. We suggest that, in LPS-treated mice, the production of NO from iNOS produces a reduction in the contractile response, as well as a decrease in NO formation by cNOS, resulting in changes to smooth muscle cell function.     

Role of inducible nitric oxide synthase in transplant arteriosclerosis

1. Transplant arteriosclerosis is a major obstacle to long-term allograft survival. Nitric oxide (NO) has been implicated as a mediator in the development of this disease. 2. We and others have shown that inducible nitric oxide synthase (iNOS) is up-regulated in allografts with transplant arteriosclerosis. Despite the acute cytotoxic effects produced by high levels of NO, a chronic increase in NO availability is protective against neointimal hyperplasia, mainly by suppressing the inflammatory cell recruitment and neointimal smooth muscle cell accumulation. 3. Currently, we have the technology to directly transfer the iNOS gene to allografts. We have demonstrated that this exciting strategy is feasible and therapeutic and may improve the long-term survival and function of allografts. Future challenges include optimizing the methods and the vectors of gene delivery.     

Expression of inducible nitric oxide synthase in trophoblasts and deciduas in early medical abortion

The purpose of this study was to investigate the expression of inducible nitric oxide synthase(iNOS) in trophoblasts and deciduas in early medical abortion, and study the relationship of medical abortion through mifepristone and iNOS in early pregnancy. Expression of iNOS in trophoblasts and deciduas was detected by both in situ hybridization and immunohistochemical assay in 40 patients (experimental group); the positive expression of iNOS was represented by number density (N/S) and positive unit (Pu) using computer color magic image analysis system (CMIAS). All results were compared with those obtained from vacuum aspiration. In the experimental group, N/S and Pu in trophoblasts were 0.120±0.010 and 15.3±2.6, respectively, while in the control group, they were 0.021±0.003 and 3.1±0.5, respectively, and there were significant differences between the two groups. By immunohistochemical assay, N/S and Pu were 0.090±0.010, 10.24±1.55 vs 0.016±0.002, 1.26±0.33 in the trophoblasts of the two groups; there were also significant differences between the two groups. There were lower iNOS expression in deciduas by in situ hybridization and immunohistochemical assay, and the difference between the two groups was not significant. It was concluded that mifepristone induced medical abortion through the expression of iNOS in trophoblasts but not in deciduas.     

Gender-specific vascular effects elicited by chronic ethanol consumption in rats: a role for inducible nitric oxide synthase

BACKGROUND AND PURPOSE: Epidemiological data suggest that the risk of ethanol-associated cardiovascular disease is greater in men than in women. This study investigates the mechanisms underlying gender-specific vascular effects elicited by chronic ethanol consumption in rats. EXPERIMENTAL APPROACH: Vascular reactivity experiments using standard muscle bath procedures were performed on isolated thoracic aortae from rats. mRNA and protein for inducible NO synthase (iNOS) and for endothelial NOS (eNOS) was assessed by RT-PCR or western blotting, respectively. KEY RESULTS: In male rats, chronic ethanol consumption enhanced phenylephrine-induced contraction in both endothelium-intact and denuded aortic rings. However, in female rats, chronic ethanol consumption enhanced phenylephrine-induced contraction only in endothelium denuded aortic rings. After pre-incubation of endothelium-intact rings with L-NAME, both male and female ethanol-treated rats showed larger phenylephrine-induced contractions in aortic rings, compared to the control group. Acetylcholine-induced relaxation was not affected by ethanol consumption. The effects of ethanol on responses to phenylephrine were similar in ovariectomized (OVX) and intact (non-OVX) female rats. In the presence of aminoguanidine, but not 7-nitroindazole, the contractions to phenylephrine in rings from ethanol-treated female rats were greater than that found in control tissues in the presence of the inhibitors. mRNA levels for eNOS and iNOS were not altered by ethanol consumption. Ethanol intake reduced eNOS protein levels and increased iNOS protein levels in aorta from female rats. CONCLUSIONS AND IMPLICATIONS: Gender differences in the vascular effects elicited by chronic ethanol consumption were not related to ovarian hormones but seemed to involve the upregulation of iNOS.     

五味子乙素对染矽尘大鼠肺组织一氧化氮水平和诱导型一氧化氮合酶mRNA表达动态变化的影响

目的观察五味子乙素(Sch-B)对染矽尘大鼠肺组织一氧化氮(NO)水平和诱导型一氧化氮合酶(iNOS)mRNA动态变化的影响。方法将96只大鼠随机分为对照组、染矽尘组、Sch-B组,每组32只,气管暴露法建立大鼠矽肺模型,造模后d 1开始灌胃给予Sch-B治疗,药物治疗3 d、7 d、14 d和28 d后,HE染色检测肺组织病理改变;硝酸还原酶法测肺组织NO含量;RT-PCR检测肺组织iNOS mRNA的表达。结果 HE染色显示Sch-B组大鼠肺损伤较染矽尘组明显减轻。NO含量和iNOS mRNA表达在染尘后各个时间点均较相应的对照组明显升高(P<0.01),其中NO含量在d 7时达到高峰后开始下降,iNOS mRNA的峰值出现在d 14。五味子组与染矽尘组相比,各时间点NO含量均明显降低(P<0.05或P<0.01),而iNOS mRNA表达仅在d 3和d 7时降低明显(P<0.05)。结论染矽尘大鼠肺组织存在着NO含量和iNOS mRNA的动态变化。Sch-B能减轻染矽尘大鼠肺组织的纤维化程度,其机制可能与染尘初期Sch-B降低iNOS mRNA转录水平,抑制NO炎症介质的合成与释放有关。