偏头痛患者血浆的一氧化氮含量的研究

目的:为了探讨NO与偏头痛的关系。方法:采用比色法测定62例偏头痛患者血浆NO的含量。结果:偏头痛患者发作期血浆NO含量明显低于正常对照组,间歇期与正常对照组比较无差异。结论:NO可能参与偏头痛发作。     

Nitrotyrosine attenuates the hemodynamic effects of adrenoceptor agonists in vivo: relevance to the pathophysiology of peroxynitrite

Peroxynitrite, which attenuates catecholamine-mediated hemodynamic responses in vivo, nitrates free tyrosine residues to form the specific product, 3-nitro- -tyrosine. The chemical structure of 3-nitro- -tyrosine is similar to that of the endogenous catecholamines. Therefore, 3-nitro- -tyrosine may interfere with catecholamine hemodynamic function in vivo. The hemodynamic responses produced by norepinephrine (1-4 μg/kg, i.v., n = 6), epinephrine (0.5-4 μg/kg, i.v., n = 7), phenylephrine (1-8 μg/kg, i.v., n = 5), and isoproterenol (100-400 ng/kg, i.v., n = 5) were attenuated, while the hemodynamic responses produced by arginine vasopressin (50-250 ng/kg; i.v., n = 5) were unaffected following the administration of 3-nitro- -tyrosine (2.5 μmol/kg, i.v.) in pentobarbital-anesthetized rats. These results demonstrate substantial and selective attenuation of the hemodynamic effects produced by - and β-adrenoceptor agonists, raising the possibility that 3-nitro- -tyrosine may play a role in the hemodynamic dysfunction associated with inflammatory conditions in which the formation of peroxynitrite is favored.     

Nitric oxide in the nucleus accumbens is involved in retrieval of inhibitory avoidance memory by nicotine

In the present study, the possible effect of nitric oxide agents injected into the nucleus accumbens (NAc) in the presence or absence of nicotine on morphine state-dependent memory in adult male Wistar rats was investigated. As a model of memory, a step-through type inhibitory avoidance task was used. Post-training injection of morphine (4 and 6 mg/kg) dose dependently induced the impairment of memory retention. Administration of morphine (4 and 6 mg/kg) before retention induced state-dependent retrieval of the memory acquired under post-training morphine (6 mg/kg) influence. Injection of nicotine before retention (0.25 and 0.5 mg/kg) alone and nicotine (0.1, 0.25 and 0.5 mg/kg) plus an ineffective dose of morphine (2 mg/kg) reversed the post-training morphine-induced memory impairment. The amnesia elicited by morphine (6 mg/kg) was also prevented by pre-retention intra-NAc administration of a nitric oxide synthase (NOS) inhibitor, l-NAME (0.24 μg/rat, intra-NAc). Interestingly, an ineffective dose of nicotine (0.1 mg/kg) in combination with low doses of l-NAME (0.06 and 0.12 μg/rat, intra-NAc) synergistically improved memory performance impaired by morphine given after training. It is important to note that intra-NAc administration of l-NAME before retention impaired memory retrieval by itself. In contrast, pre-retention administration of l-arginine, a nitric oxide (NO) precursor (0.25 and 0.5 μg/rat, intra-NAc), which had no effect alone, prevented the nicotine reversal of morphine effect on memory. The results suggest a possible role for nitric oxide of nucleus accumbens in the improving effect of nicotine on the morphine-induced amnesia and morphine state-dependent memory.     

Nitric oxide and sensory afferent neurones modulate the protective effects of low-dose endotoxin on rat gastric mucosal damage

Pretreatment (1 h) with low doses (5–40 μg/kg i.p.) of Escherichia coli endotoxin dose dependently reduced the gastric mucosal damage induced by a 10 min challenge with 1 ml ethanol (50% and 100%) in conscious rats. Treatment with the nitric oxide synthesis inhibitor, oxide synthesis inhibitor, N^G-nitro- -arginine methyl ester (L-NAME, 5 and 10 mg/kg i.p.), significantly inhibited the protective effects of endotoxin (40 μg/kg i.p.). The actions of L-NAME were reversed by the prior administration of -arginine (100 mg/kg i.p.). The protective effects of endotoxin were not influenced by pretreatment with dexamethasone (5 mg/kg s.c. twice) or indomethacin (5 mg/kg s.c.). However, ablation of sensory afferent neurones by capsaicin pretreatment (20, 30 and 50 mg/kg s.c.) abolished the mucosa protective effects of endotoxin (40 μg/kg). These findings suggest that the protection elicited by low doses of endotoxin against ethanol-induced mucosal damage involves synthesis of nitric oxide and activation of sensory neurones.     

冠心病患者血一氧化氮/一氧化氮酶和内皮素检测的临床意义

目的　探讨了 NO/ NOS和 ET在冠心病患者中的变化。方法　分别应用生化法和放免法检测了3 9例冠心病患者血 NO/ NOS和 ET含量 ,并与 3 5名正常健康人作对照。结果　冠心病患者血 NO水平低于正常人 ( P<0 .0 5 ) ,NOS和 ET水平高于正常人 ( P<0 .0 1)。结论　 NO/ NOS和 ET水平的变化与冠心病的发生与发展密切相关     

Vanadate-induced nitric oxide production: role in osteoblast growth and differentiation

Nitric oxide (NO) has been shown to act as a mediator of cytokines in bone tissue. We have previously demonstrated that vanadium compounds are insulin- and growth factor-mimetic compounds in osteoblasts in culture, although high doses are toxic to these cells. In this study, we measured NO production in two osteoblast-like cells (UMR106 and MC3T3E1) incubated with different concentrations (2.5–100 μM) of vanadate. Vanadate induced NO release in a biphasic manner, with levels being significantly increased at concentrations over 50 μM. The NO donor, sodium nitroprusside, mimicked the vanadate effect: it inhibited cell growth and alkaline phosphatase activity in a dose-dependent manner. Vanadate enhanced the NO synthases, the endothelial and inducible (eNOS and iNOS) isoforms, in a dose-dependent manner. Experiments performed with the ionophore A23187 and EGTA suggested that vanadate-induced NO production involves Ca²⁺-dependent and -independent mechanisms. Altogether, our results suggest that NO may play a critical role in the bioactivity of vanadium in osteoblast-like cells.     

Role of nitric oxide in allergic inflammation and bronchial hyperresponsiveness

The role of nitric oxide (NO) in allergic inflammation and bronchial hyperresponsiveness is unclear. We studied a selective prodrug nitric oxide synthase (NOS)-2 inhibitor, L-N(6)-(1-iminoethyl)lysine 5-tetrazole amide (SC-51). In ovalbumin-sensitized and challenged rats, exhaled NO levels increased by 3 h following challenge (3.73 +/- 0.74 ppb; P < 0.05), peaking at 9 h (11.0 +/- 2.75; P < 0.01) compared to saline controls (1.87 +/- 0.26; P < 0.05 and 2.81 +/- 0.18; P < 0.01). Immunoreactive lung NOS2 expression was increased in ovalbumin-challenged rats compared with ovalbumin-sensitized, saline-challenged rats at 8 h post-challenge. SC-51 (10 mg/kg; p.o.) inhibited allergen-induced increase in exhaled NO levels to 1.3 +/- 0.17 ppb. SC-51 inhibited bronchial hyperresponsiveness in ovalbumin-sensitized and challenged rats (P < 0.05). In sensitized non-exposed rats, SC-51 increased bronchial responsiveness (P < 0.05). SC-51 reduced the allergen-induced increase in bronchoalveolar lavage neutrophils, but caused a nonsignificant reduction in bronchial mucosal eosinophil numbers. NO generated through NOS2 contributes to allergen-induced bronchial hyperresponsiveness but not to bronchial eosinophilia, indicating that these are independently expressed.     

Nitric oxide synthase inhibitors with cardiovascular therapeutic potential

The recent patent literature concerning inhibitors of the various nitric oxide synthase (NOS) isoforms and their therapeutic potential in cardiovascular disorders is reviewed. Though the preponderance of data points to the intimate involvement of nitric oxide (NO) and the NOS isoforms in multiple cardiovascular disease states, it is not completely clear if and how NOS inhibitors with varied selectivity profiles will be beneficial. However, patents and patent applications encompassing a wide variety of structural types claim therapeutic use in cardiovascular diseases. This patent literature is examined and structural comparisons between the inhibitors and the endogenous ligands and co-factors are discussed.     

Nitric oxide influences the release of histamine and glutamate in the rat hypothalamus

To investigate the influence of nitric oxide (NO) on the release of histamine and glutamate, the anterior hypothalamus of anaesthetized rats was superfused through a push-pull cannula either with artificial cerebrospinal fluid (CSF) or with various drugs dissolved in CSF.Hypothalamic superfusion with the NO-donating compounds linsidomine (200 mol/l) or diethylamine-NO (DEANO, 100 mol/l) led to a pronounced and sustained decrease in the histamine release rate, whereas the release rate of glutamate was enhanced. Superfusion with the inhibitor of NO synthase L-N^G-nitro-L-arginine methyl ester (L-NAME, 200 mol/l) increased the histamine release rate. The inhibitory effect of 200 mol/l linsidomine was abolished by atropine (10 mol/l). Superfusion with the glutamate receptor agonists glutamate (100 mol/l) or N-methyl-D-aspartate (NMDA, 50 mol/l) enhanced the histamine release rate. In the presence of linsidomine, the releasing effect of NMDA was not changed.These findings demonstrate that the release of histamine in the hypothalamus is diminished by endogenous NO. This effect of NO on histamine release seems to be due to enhanced release of acetylcholine from vicinal cholinergic neurons via stimulation of muscarinic acetylcholine receptors located presynaptically on histaminergic neurons. The NO-induced glutamate release seems to exert a subordinate stimulatory effect on histamine release. Finally, the inhibition of histamine release by NO is not due to blockade of NMDA receptors.This work was supported by the Jubiläumsfonds der österreichischer Nationalbank     

一氧化氮对急性胰腺炎影响的研究进展

急性胰腺炎(Acute pancreatitis,AP)是一种病情凶险,病死率高的临床常见急腹症。AP的发病机制是一个复杂的、多种因素参与的病理生理过程,目前明确的发病机制尚未完全阐明。近年来,大量研究表明一氧化氮(Nitric oxide,NO)在急性胰腺炎的发生发展中起重要的作用。本文就NO对AP的影响作一综述。     

Balloon angioplasty and induction of non-endothelial nitric oxide synthase in rabbit carotid arteries

The purpose of the study was to evaluate whether balloon angioplasty is associated with changes in nitric oxide synthase (NO synthase) activity. Normal rabbit carotid arteries were examined 10 min or 1, 2, 3 or 10 weeks after angioplasty with 2 or 2.5-mm balloons. Immunohistology was used to evaluate intimal thickening and endothelial cell regeneration. The NO synthase activity was studied functionally using isolated segments in organ chambers. Immunohistochemistry of the endothelial cell markers von Willebrand factor and platelet endothelial cell adhesion molecule-1 indicated that the regeneration of endothelial cells from patchy islands that remained after angioplasty was virtually complete within 2 weeks. However, the endothelium-dependent relaxations elicited by acetylcholine remained impaired up to 10 weeks after dilatation. Contractions elicited by 5-hydroxytryptamine (5-HT) were attenuated, but were significantly augmented by the NO synthase blocker, nitro- -arginine. Furthermore, in contrast to normal arteries, the balloon-treated arteries developed marked contractions in response to nitro- -arginine methyl ester ( -NAME), contractions which could be reversed by -arginine. The latter contractions and relaxations were not influenced by endothelial removal. These results suggest that although the endothelium quickly regenerates after severe balloon injury, the endothelium-dependent release of nitric oxide remains disturbed. However, the functional data also suggest that angioplasty led to a significant induction of NO synthase in ‘non-endothelial’ cells of the artery.     

雄激素对大鼠主动脉一氧化氮合酶/一氧化氮体系的调节

目的：研究雄激素对大鼠主动脉一氧化氮合酶／一氧化氮(NOS／NO)体系的影响，以探讨雄激素对心血管系统的作用。方法：将30只雄性大鼠随机分为三个组，每组10只，去卵巢组(A组)、去卵巢 雄激素组(B组)、假手术组(C组)。正常饮食2个月后处死大鼠，测血清雄激素、主动脉匀浆一氧化氮合酶活性及一氧化氮含量。结果：同假手术组相比。去势大鼠主动脉匀浆NOS活性及NO含量显著降低，在补充适量的雄激素后．主动脉匀浆NOS活性及NO含量显著上升。结论：雄激素可以调节大鼠动脉内一氧化氮合酶／一氧化氮体系，可能是其调节血管张力的作用机制。     

四逆汤对失血性休克家兔一氧化氮（NO）和一氧化氮合酶（NOS）的影响

目的：探讨中药四逆汤对失血性休克家兔一氧化氮的影响。方法：采用动物分组对照实验，测量不同状态下动物血浆一氧化氮和一氧化氮合酶(NOS)的变化。结果：与休克前比较，休克组的家兔血浆一氧化氮水平各时段均明显提高(P＜0．01)，而治疗组仅在治疗后30min家兔一氧化氮及NOS水平明显提高(P＜0．01)，其他时段与休克前比较，未见显著差异(P＜0．01)，且休克后lh、4h、8h休克组一氧化氮水平显著高于治疗组(P＜0．01)。经药物治疗的失血性休克家兔血浆一氧化氮水平明显降低。     

Effects of a nitric oxide donor on behavior and interaction with nitrous oxide in the mouse light/dark exploration test

There is controversy whether endogenous nitric oxide (NO) is involved in anxiogenesis or anxiolysis. This study was conducted to determine the influence of the NO donor, 3-morpholinosyndnonimine (SIN-1), on resting and nitrous oxide (N(2)O)-induced behaviors in the mouse light/dark exploration test. I.c.v. doses of 0.3 and 1.0 microg SIN-1 both increased the time spent in the light compartment. When pretreated with 0.1 microg SIN-1, mice responded to N(2)O with an apparent additive increase in the time spent in the light compartment. These findings further support a functional role of NO in regulation of anxiety and mediation of N(2)O-induced behavior.     

Small-molecular virulence inhibitors show divergent and immunomodulatory effects in infection models of Salmonella enterica serovar Typhimurium

The virulence-associated Salmonella pathogenicity island 2 (SPI2) type III secretion system supports intracellular replication of Salmonella enterica serovar Typhimurium in macrophage-like RAW264.7 cells. In contrast, the salicylidene acylhydrazide INP0010 and the benzimidazole omeprazole prevent virulence factor-mediated replication of S. Typhimurium in these cells. Here we show that INP0010 enhances expression of inducible nitric oxide synthase (iNOS), nitric oxide (NO) production, the oxidative burst and tumour necrosis factor-alpha (TNFα) release in infected RAW264.7 cells. INP0010 also inhibited SPI2 activity in RAW264.7 cells. The ability of INP0010 to suppress bacterial intracellular replication correlated with NO production. The iNOS inhibitor N-monomethyl-l-arginine restored SPI2 activity and antagonised the bacteriostatic effect of INP0010. Omeprazole, which inhibited iNOS expression in RAW264.7 cells, likewise antagonised INP0010. In infected epithelioid MDCK cells that did not express NO upon infection, INP0010 enhanced bacterial intracellular replication. In Caenorhabditis elegans, INP0010 significantly attenuated the virulence of S. Typhimurium. In this infection model, the attenuating effect of INP0010 was further enhanced by omeprazole. These results demonstrate that chemically unrelated virulence inhibitors may act in an antagonistic or additive manner, that their effect depends on the infection model applied, and that the attenuating effects of INP0010 in part relate to its ability to promote the SPI2 antagonist NO.     

热毒清对内毒素性发热家兔体温及血浆NO的影响

目的观察热毒清对内毒素性发热家兔的体温以及血浆NO水平的影响,并比较不同剂量的药效。方法采用内毒素注射的方法制成发热家兔模型60只,随机分为6组,阿司匹林组(A组),热毒清高剂量组(B组),热毒清中剂量组(C组),热毒清低剂量组(D组),双黄连口服液组(E组),对照组(F组),每组10只,观察比较各组体温变化。结果与对照组比较,热毒清中剂量组及热毒清高剂量组对发热家兔的体温有明显的降温作用,且比阿司匹林组作用持续时间延长;热毒清低剂量组及双黄连组对发热家兔的体温无明显的降温作用。结论热毒清高剂量及热毒清中剂量能够降低内毒素性发热家兔的体温,改善症状和体征,降低血浆NO水平。作用机理可能是调控细胞因子网络,抑制循环血中NO的产生。     

Potentiation of anandamide effects in mesenteric beds isolated from bile duct-ligated rats: role of nitric oxide

Changes in vascular responsiveness are proposed as the basis for some of the cardiovascular complications in cholestasis. Cholestasis is also associated with accumulation of endogenous opioid peptides and evidence of nitric oxide (NO) overproduction. On the other hand, it is well known that anandamide, an endogenous cannabinoid ligand, causes hypotension and a decrease in systemic vascular resistance. In the present study, the possible role of the cannabinoid system in cholestasis-induced mesenteric vascular bed responsiveness was investigated. Mesenteric arteries of bile duct-ligated and sham-operated rats receiving daily administrations of saline were used for evaluating phenylephrine or anandamide dose-response, acute effects of N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM), a non-selective inhibitor of NO synthase (NOS), or naltrexone, an opioid receptors antagonist (1 microM). The other groups of bile duct-ligated and sham-operated rats received daily intraperitoneal administration of L-NAME (20 mg/kg/day), aminoguanidine, a selective inducible NOS (iNOS) inhibitor (150 mg/kg/day) or naltrexone (10 mg/kg/day). After 7 days, the superior mesenteric artery was cannulated and the mesenteric vascular bed was perfused according to the McGregor method. Anandamide-induced relaxation was significantly potentiated in mesenteric vascular beds of bile duct-ligated rats. Chronic treatment of bile duct-ligated animals with L-NAME and aminoguanidine blocked this hyperresponsiveness while the hyperresponsiveness was potentiated at large doses of anandamide on chronic treatment of these animals with naltrexone. Although acute L-NAME treatment of mesenteric beds completely blocked the anandamide-induced vasorelaxation in sham-operated rats, this vasorelaxation still was present in bile duct-ligated animals. Anandamide-induced vasorelaxation remained unaffected after acute naltrexone treatment of mesenteric beds in both bile duct-ligated and sham-operated rats. Our results indicate that (1) there is enhanced anandamide-induced vasorelaxation in cholestatic rats, probably due to a defect in cannabinoid or vanilloid receptors and (2) NO overproduction may be involved in cholestasis-induced vascular hyperresponsiveness.     

一氧化氮在顺铂致大鼠肾损害过程中的作用

目的 探讨一氧化氮在顺铂肾毒性氧化应激机制中的作用。方法 采用少量多次给大鼠腹腔注射顺铂（ＣＰ）及经口给予水飞蓟素（ＳＢ）预处理后给予ＣＰ模型,观察血尿素氮（ＢＵＮ）含量、一氧化氮合酶（ＮＯＳ）活性、丙二醛（ＭＤＡ）形成、超氧化物歧化酶（ＳＯＤ）活性等指标的变化。结果 ＣＰ可诱导ＮＯＳ活性增高,使ＮＯ生成量增多;ＢＵＮ含量与ＭＤＡ含量及ＳＯＤ活性的变化并不完全一致,而与ＮＯ含量的时相变化活性增高,