Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.6.5.2 (NQO1)
 6,196 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transgenic mice (Tg2576) that express the Swedish double mutation of human amyloid precursor protein and develop Alzheimer-like beta-amyloid deposits in the aged brain, were used to study the effect of beta-amyloid deposition on expression of both neuronal (nNOS) and inducible nitric oxide synthase (iNOS) in cells surrounding beta-amyloid plaques. Nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry and double immunofluorescent labeling revealed that most of the fibrillary, thioflavine-S-positive cortical beta-amyloid deposits in 13-, 17-, and 21-month-old transgenic animals were closely associated with dystrophic nNOS-positive neurons, while nNOS-bearing neurons located more distal to plaques appeared to be unaffected. There was no significant expression of iNOS in transgenic mouse brain. The data suggest enhanced vulnerability of nNOS-containing neocortical neurons to beta-amyloid toxicity. Alternatively, expression of nNOS may also be a response to plaque-mediated damage of neurons, consistent with a neuroprotective role of nitric oxide.
 ...
PMID:Fibrillary beta-amyloid deposits are closely associated with atrophic nitric oxide synthase (NOS)-expressing neurons but do not upregulate the inducible NOS in transgenic Tg2576 mouse brain with Alzheimer pathology. 1129 Mar 90

Several studies reported the morphology of calretinin-positive (CR+) neurons and nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) labeled or neuronal nitric oxide synthase-positive (nNOS+) neurons in the rodent hippocampus, where these neurons showed similar morphological features. In addition, a previous study reported the frequent colocalization of CR and NADPH-d in the rat hippocampus. In this study, we aimed to examine whether CR+ neurons and nNOS+ neurons belong to a same morphological subpopulation of GABAergic neurons in the mouse hippocampus. Neurons were immunocytochemically classified into three groups, i.e., CR+/nNOS-, CR-/nNOS+ and CR+/nNOS+ groups. The present morphometric analysis was performed in the mouse Ammon's horn, because CR+/nNOS+ neurons were rarely found in the mouse dentate gyrus. We selected three morphometric parameters, i.e., soma area, soma form factor (FF) and number of primary dendrites. Dunnett's post-hoc analysis revealed that soma area, soma FF and number of primary dendrites were significantly larger in CR-/nNOS+ group than in CR+/nNOS- and CR+/nNOS+ groups. The morphometric data of CR+/nNOS+ group were quite similar to those of CR+/nNOS- group. The morphometric multivariate logistic regression analysis revealed that these three morphometric parameters were independent significant variables to discriminate between CR+/nNOS- and CR-/nNOS+ groups, and the majority of CR+/nNOS- and CR-/nNOS+ groups were correctly classified from the morphometric features. The present results clearly indicate that CR+/nNOS- neurons and CR-/nNOS+ neurons belong to different morphological subpopulations, and lead us to speculate that they might play different functional roles in the hippocampal circuit. The further application of morphometric multivariate analysis would be valuable to understand the functional roles of chemically defined neurons in the various brain regions.
 ...
PMID:Morphometric multivariate analysis of GABAergic neurons containing calretinin and neuronal nitric oxide synthase in the mouse hippocampus. 1133 98

Nitric oxide has proven to be an important mediator in the relaxation of human cavernosal smooth muscle. Nevertheless, there are many inconsistencies in the literature regarding the cellular and subcellular distribution of endothelial nitric oxide synthase in the human penis. The purpose of this study was to reexamine the localization of eNOS and nNOS in the cellular anatomy of the human cavernous body by means of electron microscopical immunocytochemistry in combination with the tyramide signal amplification technique (TSA). Using specific antibodies against eNOS and nNOS, the NAPDH-diaphorase reaction and advanced protocols for fixation and staining procederes, the occurrence of NOS isoenzymes eNOS and nNOS were examined in cavernosal specimens of ten male patients who were subjected to surgery for penile deviation. eNOS immunoreactivity and NADPH-d staining was seen to be significantly present in the endothelial cells covering the cavernous spaces and in the endothelium of helicine arteries. In endothelial cells, the NADPH-d reaction product BSPT-formazan was abundantly detectable attached to membranes of the endoplasmatic reticulum and the mitochondria whereas posititve eNOS immunostaining was seen in the endothelial cells throughout their cytoplasm without any particular relation to organelles. No considerable eNOS immunoreactivity was detectable in the trabecular smooth muscle cells. nNOS staining was found in nerve fibers innervating the cavernous body and cavernosal arteries. Our results counteract the hypothesis of the cavernous smooth muscle as a local source of NO and underline the importance of an intact endothelial function for penile erection and the contribution of eNOS to this process.
 ...
PMID:Immunocytochemical distribution of nitric oxide synthase in the human corpus cavernosum: an electron microscopical study using the tyramide signal amplification technique. 1148 40

The aim of this study was to describe the anatomic distribution of neuronal nitric oxide synthase immunoreactivity (nNOS-IR) and nicotinamide-adenine dinucleotide phosphate-diaphorase (NADPH-d) staining in the olfactory epithelium of the axolotl, juvenile, and neotenic adult, Ambystoma mexicanum. Nitric oxide (NO, nitrogen monoxide) is a widespread molecule that has been identified both as a neuromodulator and as an intracellular messenger. In the olfactory system, NO has been proposed to play a role in olfactory transduction. Nitric oxide synthase (NOS) can be detected by histochemical (NADPH-d) and immunohistochemical techniques. NADPH-d staining has been described in olfactory receptor neurons (ORN) of several species; however, nNOS-IR has not always been found at ORN. Present results show intense NADPH-d staining and nNOS-IR in the dendrites and cell bodies of ORN in both the nasal cavity and the vomeronasal organ of axolotls. Unilateral olfactory axotomy was conducted to confirm that labels were at ORN. Two weeks after this procedure an important decrease in NADPH-d staining and nNOS-IR was observed. The remaining labels were mostly in basal cells. By 5 weeks postaxotomy both labels were almost totally absent. Thus, both NADPH-d staining and nNOS-IR were mainly localized in ORN. NADPH-d staining and nNOS-IR were also found in nerve fibers surrounding arterioles, as well as in secretory and duct cells of the Bowman's glands. This last anatomical localization suggests that in the A. mexicanum NO might be involved in functions other than only olfactory transduction, such as regulation of local blood flow, glandular secretion, and ORN development.
 ...
PMID:Histochemical and immunohistochemical localization of neuronal nitric oxide synthase in the olfactory epithelium of the axolotl, Ambystoma mexicanum. 1148 69

This study was aimed to determine whether axotomy coupled with hypoxia would exert a more profound effect on injury-induced neuronal nitric oxide synthase (NOS) expression. In this connection, the vagus and the hypoglossal nerves of adult rats were transected unilaterally in the same animal, and half of the operated animals were subjected to hypoxia treatment. Both the neuronal NOS immunohistochemistry and the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry were used to assess the neuronal NOS expression. The present results have shown that the number of NADPH-d/NOS-positive [NADPH-d/NOS(1)] neurons in the hypoglossal nucleus (HN) peaked at 14 days after axotomy, while that in dorsal motor nucleus of vagus (DMN) and nucleus ambiguus (NA) was progressively increased up to 60 days. The up-regulation of NADPH-d/NOS in HN and DMN was more pronounced in hypoxic than in normoxic animals, a feature that was not evident in the NA. Quantitative analysis showed that the number of surviving motoneurons in normoxic animals was significantly higher than those subjected to hypoxia at 14 days postaxotomy in HN and at all postaxotomy time points in DMN. The difference may be attributed to their different functional components. Since O2 deprivation leads to poor cellular function, the stronger expression of NADPH-d/NOS and the more drastic neuronal loss following nerve transection in the hypoxic animals compared with the controls suggest that hypoxia plays an important role in peripheral neuropathies in which NO is implicated.
 ...
PMID:Axotomy along with hypoxia enhances the neuronal NADPH-d/NOS expression in lower brain stem motor neurons of adult rats. 1152 Jan 26

The aim of this study was to investigate the electroacupuncture-related changes of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) and neuronal nitric oxide synthase (nNOS) in the brainstem of spontaneously hypertensive rats (SHR). We evaluated the changes of NADPH-d-positive neurons using a histochemical method and the changes of nNOS-positive neurons using an immunohistochemical method. The staining intensities of NADPH-d-positive neurons and nNOS-positive neurons were assessed in a quantitative fashion using a microdensitometrical method based on optical density by means of an image analyzer. The optical density of NADPH-d-positive neurons and nNOS-positive neurons of the Shinsu (BL23) and Choksamni (ST36) electroacupuncture groups were significantly decreased in most brainstem areas as compared to the normal and arbitrary groups, with the exception of the optical density of NADPH-d positive neurons in the prepositus nucleus as compared to the arbitrary group. The present results demonstrated that electroacupuncture changes the activity in the NO system in the brainstem of SHR and the site where electroacupuncture is administered is of importance for this effect.
 ...
PMID:Electroacupuncture-related changes of NADPH-diaphorase and neuronal nitric oxide synthase in the brainstem of spontaneously hypertensive rats. 1159 35

In this study, the responses of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) and neuronal nitric oxide synthase (nNOS) activities were quantitatively analyzed at different times in both ipsilateral and contralateral sides of trigeminal nuclei, after unilateral trigeminal muscle nerve transection, in Sprague Dawley rats. In the control animals, both NADPH-d- and nNOS-positive neurons were constitutively distributed in the rostrolateral solitary tract nucleus, dorsomedial part of trigeminal nucleus oralis (Vo/Sn), and superficial layers (VcI/II) of the trigeminal nucleus caudalis (Vc). NADPH-d-positive neurons appeared in the trigeminal mesencephalic nucleus ipsilaterally at 5 days (mean +/- SEM: 30.5 +/- 5.6) and were maintained until 8 weeks (33 +/- 10.6) after the denervation. In the trigeminal motor nucleus, NADPH-d-positive neurons appeared transiently and bilaterally, peaking at 1 week (663.5 +/- 156.2, ipsilateral side; 687.5 +/- 118.6, contralateral side) after unilateral denervation of the masseteric nerve. In both Vo/Sn and Vc, the number of NADPH-d-positive neurons in the control animals showed a decrease at 3 days but significantly increased from 5 days to 1 week and gradually fell to the control values by 8 weeks after the denervation. There were no significant differences observed between the two sides in either Vo/Sn or Vc. nNOS-positive neurons were similarly distributed and the numbers of labeled neurons were similar to those of NADPH-d-positive neurons after the denervation, although the changes were delayed by approximately 1 week. In conclusion, after unilateral nerve transection, the peak NADPH-d activity occurs 1 week prior to nNOS activity.
 ...
PMID:Nitric oxide synthase/nicotinamide adenine dinucleotide phosphate-diaphorase in the brainstem trigeminal nuclei after transection of the masseteric nerve in rats. 1174 60

Since the interneuronal messenger nitric oxide (NO) can not be stored in neurones, the regulation of the NO-producing enzyme nitric oxide synthase (NOS) is crucial. Neuronal NOS metabolises L-arginine to nitric oxide (NO) and L-citrulline in a Ca(2+)-dependent manner. Thus, availability of L-arginine to NOS may modulate NO production. In this study, we examined the cellular distribution of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase, L-arginine and L-citrulline. Using NADPH-diaphorase histochemistry to visualise putative NO-producing cells and immunocytochemistry to localise L-arginine, we showed that the distribution of L-arginine-immunoreactive neurones correlates well with those of NADPH-diaphorase-positive neurones in cerebral ganglia of the pulmonate Helix pomatia. However, substrate and enzyme were visualised in separate but adjacent neurones. We further examined whether NADPH-diaphorase-labelled cells contain the L-citrulline. Following elevation of intracellular Ca(2+) by the Ca(2+) ionophore, ionomycin, or by a high-K(+) solution, the number of L-citrulline-immunoreactive neurones in mesocerebrum and pedal lobe increased up to tenfold. Preincubation of ganglia with the NOS inhibitor N(G)-nitro-L-arginine prevented ionomycin or high-K(+) solution-induced L-citrulline synthesis. Most L-citrulline-immunoreactive neurones contain NADPH-diaphorase activity. In conclusion, these experiments indicate a complementary distribution of NOS and L-arginine and suggest an unknown signalling pathway between neurones to maintain L-arginine and NO homeostasis.
 ...
PMID:Complementary distribution of NADPH-diaphorase and l-arginine in the snail nervous system. 1190 76

Neuronal nitric oxide is a non-adrenergic non-cholinergic neurotransmitter in the enteric nervous system and plays a role in a variety of enteropathies including Crohn's and Chagas' diseases, ulcerative colitis, diabetes, atrophy and hypertrophy. The content of neuronal nitric oxide synthase (nNOS) in the colon and the caecum from pigs infected with Schistosoma japonicum was studied using immunohistochemical and histochemical staining for nNOS and nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase), respectively. In the infected pigs, lightly, moderately and less severely inflamed tissues showed increased nNOS and NADPH-diaphorase activities in nerve cell bodies and nerve fibres in the enteric plexuses compared to control pigs. There was a significant increase in the nerve cell body density of nNOS immunoreactive nerve cell bodies in the inner submucous plexus, outer submucous plexus and in the myenteric plexus. More intensely stained nerve cell bodies and varicosities were observed in tissue from prenatally infected and prenatally infected, postnatally re-infected pigs compared to postnatally infected pigs. However, the latter showed the highest numerical density of nNOS immunoreactive nerve cell bodies. Marked increases were seen in the inner submucous plexus followed by myenteric plexus, inner circular muscle, outer submucous plexus and mucous plexus. However, in very severe inflamed tissues, the number and staining intensity of nerve cell bodies and nerve fibre varicosities were reduced in plexuses located in the lesions with the inner submucous and mucous plexuses being the most affected. There was no staining in the nervous tissue within the eosinophilic cell abscesses and productive granulomas. The apparent alterations in the activities of enzymes responsible for the generation of nitric oxide (NO) show possible alterations in the NO mediated non-adrenergic non-cholinergic reflexes in the enteric nervous tissue. These alterations might contribute to impaired intestinal motility and absorption, and other pathophysiological conditions seen during S. japonicum infections.
 ...
PMID:Neuronal nitric oxide synthase activity is increased during granulomatous inflammation in the colon and caecum of pigs infected with Schistosoma japonicum. 1217 Dec 50

Reflux nephropathy (RN) is recognized as a major cause of end-stage renal failure in children and young adults. Inhibition of nitric oxide (NO) exacerbates and enhanced production ameliorates tubulointerstitial fibrosis (TIF) in experimental obstructive uropathy. NO is synthesised by NO synthase (NOS), three distinct isoforms of which have been identified: inducible (iNOS), endothelial (eNOS), and neuronal (nNOS). It has been reported that iNOS induces immunologic injury to glomerular cells and enhances accumulation of extracellular matrix in the glomerulus and tubulointerstitial space. Furthermore, it has been suggested that nNOS and eNOS have beneficial effects in ameliorating TIF. We investigated the expression of different isoforms of NOS in severe refluxing kidneys in order to further understand the pathogenesis of RN in kidney specimens from nine children with severe RN obtained at nephrectomy. Control material included normal kidney specimens from three adult patients undergoing partial nephrectomy for small kidney tumours. Histochemistry for NO was performed using nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase. Single-label immunofluorescence histochemistry was carried out using polyclonal antibodies to nNOS, iNOS, eNOS, and transforming growth factor (TGF)-beta 1 employing laser-scanning confocal microscopy. The TUNEL method was used to assess tubular apoptosis. Strong NADPH staining was observed in the proximal tubules of RN kidneys compared to controls, where there was weak staining. Control kidneys demonstrated weak immunoreactivity for iNOS in the proximal tubules and a lack of immunoreactivity for nNOS and eNOS. RN kidneys demonstrated strong immunoreactivity for nNOS in the tubulointerstitial space, for eNOS in the glomerulus, and for iNOS in the glomerulus and proximal tubules. Strong immunoreactivity for TGF beta 1 was seen in the glomerulus and proximal tubules identical to iNOS. Increased immunoreactivity for iNOS and TGF-beta 1 strongly correlated with the severity of apoptosis in RN. Our data demonstrate that NO derived from nNOS, iNOS, and eNOS is strongly expressed in RN. The selective shunting of NO via iNOS may induce renal fibrosis in RN. The upregulation of nNOS and eNOS in RN appears to be a compensatory mechanism of ameliorating TIF.
 ...
PMID:The role of nitric oxide in reflux nephropathy. 1247 80


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>