一氧化氮/一氧化氮合酶与神经创伤

一氧化氮(NO)是一种简单的气体分子,可在哺乳类神经细胞内经一氧化氮合酶(NOS)作用产生.NO在神经创伤与修复中的多重作用近年来已受到越来越多的重视.本文对NO/NOS与神经创伤和再生之间的关系作一综述.     

海人酸致痫动物模型脑内一氧化氮,一氧化氮合酶的变化

目的探讨一氧化氮（ＮＯ）、一氧化氮合酶（ＮＯＳ）在癫痫发生中的作用及ＮＯＳ抑制剂的作用。方法采用海人酸致痫大鼠模型并应用ＮＯＳ抑制剂Ｌ－硝基精氨酸甲酯（Ｌ－ＮＡＭＥ）,分别在致痫后３０分钟、６０分钟取海马组织,匀浆后测定ＮＯ及ＮＯＳ水平。结果致痫３０分钟后海马ＮＯ含量显著升高,至６０分钟恢复正常;ＮＯＳ活性水平增高＞５０％;Ｌ－ＮＡＭＥ明显抑制大鼠的痫性发作,应用ＮＯＳ抑制剂组大鼠海马ＮＯ、ＮＯＳ含量明显下降。结论癫痫发作后脑内ＮＯ、ＮＯＳ活性增强,ＮＯＳ抑制剂通过抑制酶活性使ＮＯ生成降低,并完全抑制痫性发作。ＮＯＳ活性受抑制＞４８％即可产生明显效果。提示ＮＯ可能有内源性致痫作用。     

一氧化氮与帕金森病大鼠模型神经损伤的研究

目的 研究一氧化氮（ＮＯ）在帕金森病（ＰＤ）大鼠模型神经损伤中的作用。方法 用高效液相色谱电化学法（ＨＰＬＣ－ＥＴ）及还原型辅酶Ⅱ（ＮＡＤＰＨ）黄递酶组化法观察ＮＯ在ＰＤ大鼠模型神经损伤中的作用。结果 神经型一氧化氮合成酶（ｎＮＯＳ）抑制剂７－硝基吲唑（７－ＮＩ）明显减少６－羟基多巴胺（６－ＯＨＤＡ）引起的纹状体多巴胺及其代谢产物的降低（Ｐ〈０．０１）；纹状体ＮＡＤＰＨ黄递酶阳性神经元可抵抗６－Ｏ     

一氧化氮与缺血性神经元损伤

一氧化氮与缺血性神经元损伤柯开富，包仕尧，张树生１９９２年一氧化氮（ＮＯ）被美国科学杂志［１］评选为“今年的分子”，表明ＮＯ在生命科学界的重大价值。ＮＯ是结构简单的气体物质，易扩散，反应性强，易溶于水，半衰期仅几秒。ＮＯ在哺乳动物体内的作用最先是由Ｆ...     

一氧化氮与中枢神经系统寄生虫病

Ｆｕｒｃｈｇｏｔｔ和Ｚａｗａｄｚｋｉ首次发现内皮细胞可产生一种使血管舒张的物质 ,最初将之命名为“内皮性舒张因子”(Ｅｎ ｄｏｔｈｅｌｉｕｍ ｄｅｒｉｖｅｄｒｅｌａｘｉｎｇｆａｃｔｏｒ) [1] ;以后证实是一氧化氮 (Ｎｉｔｒｉｃｏｘｉｄｅ ,ＮＯ)分子[2 ] 。事实上 ,人体内许多其他细胞(如巨噬细胞、中性粒细胞、星形细胞、小胶质细胞等 )也可合成ＮＯ。ＮＯ是一种高脂溶性的小分子 ,有许多生物学功能 ,如调节脑血流量 ,抗血小板聚集和白细胞粘附 ,参与神经突触的信息传递 ,发挥细胞毒性作用等。ＮＯ合成的底物为Ｌ 精氨酸和Ｏ2 ,…     

一氧化氮生物作用的双面性与缺血性脑损伤

一氧化氮（ＮＯ）既是一种信使分子，又是一种神经毒素，越来越多的研究表明其可能参与了缺血性脑损伤的病理生理机制。尽管最初关于ＮＯ在脑缺血中作用的研究结果具有争议性，但随着选择性药理学工具的开发以及一氧化氮合酶（ＮＯＳ）基因缺陷小鼠的应用，ＮＯ在脑缺血中...     

一氧化氮与癫痫的研究进展

一氧化氮与癫痫的研究进展陈晋文孙长凯黄远桂癫痫是神经系统常见病，不仅危害人类健康，而且带来一系列复杂的社会问题。近年来，随着生理学、病理形态学和生物化学研究的深入，以及一氧化氮（ＮＯ）的发现，再次为癫痫研究开辟了一条新的途径。ＮＯ是一种不寻常的生物信...     

一氧化氮合酶与局灶性脑缺血

缺血性神经元损害的病理生理机制迄今为止尚未完全阐明，可能与多种致病因素有关，如谷氨酸（Ｇｌｕ）过量释放、细胞内Ｃａ２＋超载、自由基产生等。近年来研究发现，一氧化氮（ＮＯ）在中枢神经系统损害中发挥着重要作用，而且来源于不同类型一氧化氮合酶（ＮＯＳ）的Ｎ...     

大鼠脑缺血时脑组织中NOS1阳性神经元变化的连续观察

目的探讨脑缺血时含神经型一氧化氮合成酶（ＮＯＳ）神经元变化及一氧化氮（ＮＯ）的相关作用。方法采用大脑中动脉梗塞模型，对３４只雄性ＳＤ大鼠脑缺血后不同时点ＮＯＳ１免疫组化、ＮＡＤＰＨ－ｄ染色及其病理学进行了对照研究。结果缺血后２～４８小时，梗塞侧的ＮＯＳ１神经元数量明显高于对侧，４小时达高峰。梗塞后２４～４８小时，神经元出现边界不清、膨胀，而含ＮＯＳ１神经元则保持形态学的完整性。１周时，大部分神经元死亡，但仍有完整的ＮＯＳ１阳性细胞散在。结论含ＮＯＳ１神经元对脑缺血有一定的抵抗能力，可能与ＮＯ的神经保护作用有关     

一氧化氮与吗啡依赖

一氧化氮（ＮＯ）参与吗啡依赖及戒断症状发生的过程，ＮＯ合酶抑制剂可望有于戒毒。     

青白散对慢性软组织损伤模型大鼠骨骼肌一氧化氮合酶系统和一氧化氮的影响*☆

背景：对慢性软组织损伤后一氧化氮合酶系统和一氧化氮的研究目前较少。 目的：观察青白散对大鼠慢性软组织损伤模型骨骼肌中一氧化氮合酶系统和一氧化氮的影响。 方法：雄性 SD 大鼠随机分为对照组、模型组、氨基胍组、青白散组。后3组采用机械损伤法制备慢性骨骼肌损伤动物模型,分别予以生理盐水 10 mL/kg,0.10 g/kg氨基胍,0.54 g/kg青白散,1次/d,连续 14 d。于给药后1,2,3周,分别检测大鼠肌组织一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性。 结果与结论：骨骼肌损伤修复过程中,模型组大鼠骨骼肌中一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性较对照组显著增高;而青白散组和氨基胍组大鼠骨骼肌中一氧化氮含量、总一氧化氮合酶和诱导型一氧化氮合酶的活性均较模型组显著降低。说明青白散可能通过阻抑诱导型一氧化氮合酶诱导过量一氧化氮的产生,为慢性软组织损伤的修复创造了有利条件。     

Differences in peripheral nerve degeneration/regeneration between wild-type and neuronal nitric oxide synthase knockout mice

Nitric oxide (NO), a unique biological messenger molecule, is synthesized by three isoforms of the enzyme NO synthase (NOS) and diffuses from the site of production across cellular membranes. A postulated role for NO in degeneration and regeneration of peripheral nerves has been explored in a sciatic nerve model comparing wild-type mice and mice lacking neuronal NOS after transection and microsurgical repair. In NOS knockout mice, regenerative delay was observed, preceded by a decelerated Wallerian degeneration (WD). In the regenerated nerve, pruning of uncontrolled sprouts was disturbed, leading to an enhanced number of axons, whereas remyelination seemed to be less affected. Delayed regeneration was associated with a delayed recovery of sensor and motor function. In such a context, possible NO targets are neurofilaments and myelin sheaths of the interrupted axon, filopodia of the growth cone, newly formed neuromuscular endplates, and Schwann cells in the distal nerve stump. The results presented suggest that 1) local release of NO following peripheral nerve injury is a crucial factor in degeneration/regeneration, 2) success of fiber regeneration in the peripheral nervous system depends on a regular WD, and 3) manipulation of NO supply may offer interesting therapeutic options for treatment of peripheral nerve lesions.     

局灶性鼠脑缺血时一氧化氮及一氧化氮合酶抑制剂的作用机制

目的研究一氧化氮在鼠脑局灶性脑缺血再灌注损伤中的作用。方法用线栓法建立大鼠大脑中动脉区缺血再灌注模型，分别用选择性和非选择性诱导型一氧化氮合酶抑制剂对鼠脑局灶性缺血再灌注过程中脑组织一氧化氮的变化规律及可能作用进行探讨。结果非选择性一氧化氮合酶抑制剂（Ｌ－ＮＡＭＥ）可加重局灶性脑缺血性损害，而选择性诱导型一氧化氮合酶抑制剂（ａｍｉｎｏｇｕａｎｉｄｉｎｅ，ＡＧ）具有明确的脑保护作用。结论不同类型的一氧化氮合酶所产生的一氧化氮在脑局灶性缺血性损害中具有不同的作用。     

Neuronal nitric oxide synthase expression in cerebellar mutant mice

Nitric oxide (NO) is a diffusible, multifunctional signaling molecule found in many areas of the brain. NO signaling is involved in a wide array of neurophysiological functions including synaptogenesis, modulation of neurotransmitter release, synaptic plasticity, central nervous system blood flow and cell death. NO synthase (NOS) activity regulates the production of NO and the cerebellum expresses high levels of nitric oxide synthase (NOS) in granule, stellate and basket cells. Cerebellar mutant mice provide excellent opportunities to study changes of NO/NOS concentrations and activities to gain a greater understanding of the roles of NO and NOS in cerebellar function. Here, we have reviewed the current understanding of the functional roles of NO and NOS in the cerebellum and present NO/NOS activities that have been described in various cerebellar mutant mice and NOS knockout mice. NO appears to exert neuroprotective effects at low to moderate concentrations, whereas NO becomes neurotoxic as the concentration increases. Excessive NO production can cause oxidative stress to neurons, ultimately impairing neuronal function and result in neuronal cell death. Based on their genetics and cerebellar histopathology, some of cerebellar mutant mice display similarities with human neurological conditions and may prove to be valuable models to study several human neurological disorders, such as autism and schizophrenia.     

Transient action of the endothelial constitutive nitric oxide synthase (ecNOS) mediates the development of thermal hypersensitivity following peripheral nerve injury

Neuropathic pain is a disabling feature of peripheral nerve injury. Following injury, local inflammation and the release of mediators may contribute to ectopic mechanosensitivity of the nerve-trunk and pain hypersensitivity. In the present study we investigated whether nitric oxide (NO) action and local nitric oxide synthase (NOS) expression play a role in pain hypersensitivity and A fibre-mediated ectopic hyperexcitability following a chronic constriction injury to a rat sciatic nerve. Using immunohistochemical methods we provide evidence for a unique endothelial constitutive nitric oxide synthase (ecNOS) immunoreactivity localized in early axonal endbulb-like structures of injured peripheral nerve axons. Moreover, we show that following nerve injury there is increased ecNOS-mRNA expression within the lumbar sympathetic ganglia, and that axoplasmic transport in sympathetic and other axons rather than local non-neural synthesis accounts for its accumulation in nerve fibres. We also demonstrate here that local inhibition of NOS action with the broad-spectrum inhibitor NG-nitro-L-arginine-methyl ester (L-NAME), but not more specific inhibitors of other NOS isoforms, has stereospecific, dose- and time-dependent analgesic effects that were reversed by local administration of L-arginine, the natural precursor of NO. In further work, using a teased fibre preparation, we show that administration of L-NAME, but not D-NAME, to the injury site also blocks ectopic mechanosensitivity of injured A-fibres. Our results indicate that an early and transient local ecNOS expression within early axonal endbulb-like structures, some arising from sympathetic axons, plays a critical role in the development of neuropathic pain.     

一氧化氮合酶抑制剂对脊髓损伤后运动功能的影响

目的观察诱导型和神经型一氧化氮合酶(iNOS,nNOS)抑制剂对大鼠脊髓损伤(SCI)后运动功能的影响和机理。方法大鼠脊髓压迫伤后分别给予iNOS和nNOS抑制剂—氨基胍(AG)和7-硝基吲唑(7-NI)进行治疗,24h后用分光光度法测定组织中一氧化氮(NO)含量和一氧化氮合酶(NOS)活性,72h后用流式细胞仪检测神经细胞凋亡情况,4周后用电生理和动物行为学等指标评价运动功能的恢复情况。结果AG和7-NI均可以抑制组织中的NO含量,并使NOS活性下降,同时降低神经细胞的凋亡比率,对运动功能的恢复前者优于后者。结论脊髓损伤后应用NOS抑制剂可以使伤后运动功能得到改善,AG的作用似乎更明显,提示iNOS活性变化可能对脊髓损伤的恢复更具决定作用。     

Local isoform‐specific NOS inhibition: A promising approach to promote motor function recovery after nerve injury

Physical injury to a nerve is the most frequent cause of acquired peripheral neuropathy, which is responsible for loss of motor, sensory and/or autonomic functions. Injured axons in the peripheral nervous system maintain the capacity to regenerate in adult mammals. However, after nerve transection, stumps of damaged nerves must be surgically joined to guide regenerating axons into the distal nerve stump. Even so, severe functional limitations persist after restorative surgery. Therefore, the identification of molecules that regulate degenerative and regenerative processes is indispensable in developing therapeutic tools to accelerate and improve functional recovery. Here, I consider the role of nitric oxide (NO) synthesized by the three major isoforms of NO synthases (NOS) in motor neuropathy. Neuronal NOS (nNOS) seems to be the primary source of NO that is detrimental to the survival of injured motoneurons. Endothelial NOS (eNOS) appears to be the major source of NO that interferes with axonal regrowth, at least soon after injury. Finally, NO derived from inducible NOS (iNOS) or nNOS is critical to the process of lipid breakdown for Wallerian degeneration and thereby benefits axonal regrowth. Specific inhibitors of these isoforms can be used to protect injured neurons from degeneration and promote axonal regeneration. A cautious proposal for the treatment of acquired motor neuropathy using therapeutic tools that locally interfere with eNOS/nNOS activities seems to merit consideration. © 2010 Wiley‐Liss, Inc.     

一氧化氮合酶活性与抑郁症的相关性

目的通过对抑郁症患者一氧化氮合酶（NOS）活性进行检测，从而研究和探讨一氧化氮合酶、一氧化氮（NO）与抑郁症之间的关系。方法采用分光光度法检测抑郁症患者治疗前后的一氧化氮合酶NOS及其亚型（结构型cNOS、诱导型iNOS）的活性，并与正常对照组比较。结果抑郁症组的NOS、cNOS活性显著低于正常对照组；治疗组的NOS、cNOS活性高于抑郁症（无显著性），但治疗后缓解组的NOS、cNOS活性均显著高于治疗前。各组iNOS的活性无显著差异。结论抑郁症病人的NOS活性下降，而且主要是结构型cNOS活性下降，经治疗缓解后有所提高。因此，NOS和NO很有可能在抑郁症的发病过程中起着重要作用。     

Involvement of nitric oxide and nitric oxide synthase activity in anticonvulsive action

The anticonvulsant drug Diazepam (DIA-2 mg/kg b. wt), the nitric oxide (NO) donor L-Arginine (L-Arg-2000 mg/kg b. wt) and the putative nitric oxide synthase (NOS) inhibitor N(G)-Nitro-L-Arginine methyl ester (L-NAME-50 mg/kg b. wt) were used to determine the role of endogenous NO on convulsions induced by picrotoxin (PCT-5 mg/kg b. wt) in rats. Rats given a convulsant dose of PCT (5 mg/kg b. wt) had convulsion and it suppresses the NOS activity and NO concentration in brain regions. The anticonvulsant L-Arg alone significantly increases the NO concentration and NOS activity in brain regions, but not diazepam. Whereas DIA, along with L-Arg, enhances the NO and NOS activity when compared to L-Arg alone. The combination of both OIA and L-Arg completely suppressed the convulsions. L-NAME alone had no effect to produce convulsions but it completely decreased NO concentration and NOS activity and potentiated the PCT convulsions. This was reverted by pre- and post treatment of DIA plus L-Arg indicating, the increased NO concentration and NOS activity in brain regions suppresses convulsions.     

Nitric oxide and nitric oxide synthase in Huntington's disease

Nitric oxide (NO) is a biologically active inorganic molecule produced when the semiessential amino acid l-arginine is converted to l-citrulline and NO via the enzyme nitric oxide synthase (NOS). NO is known to be involved in the regulation of many physiological processes, such as control of blood flow, platelet adhesion, endocrine function, neurotransmission, neuromodulation, and inflammation, to name only a few. During neuropathological conditions, the production of NO can be either protective or toxic, dependent on the stage of the disease, the isoforms of NOS involved, and the initial pathological event. This paper reviews the properties of NO and NOS and the pathophysiology of Huntington's disease (HD). It discusses ways in which NO and NOS may interact with the protein product of HD and reviews data implicating NOS in the neuropathology of HD. This is followed by a synthesis of current information regarding how NO/NOS may contribute to HD-related pathology and identification of areas for potential future research.