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

NADPH-diaphorase activity, which has been previously reported to be associated with the enzyme nitric oxide synthase (NOS), was localized cytochemically in the pancreatic islets of normal rats. All islet cells types, i.e. insulin-, glucagon-, somatostatin- and pancreatic polypeptide-immunoreactive cells, expressed NAD-PH-diaphorase histochemical activity, whereas the exocrine tissue was almost negative. In streptozotocin-treated rats, only the surviving non-beta cells in the islet periphery were stained. Isolated beta and non-beta cells also expressed intense NADPH-diaphorase activity. By electron microscopy, the enzyme was localized primarily on membranes of the endoplasmic reticulum and nuclear envelope, as previously reported for neurons. In addition the enzyme activity was found in the cis-region of the Golgi complex. These results suggest that the four types of endocrine cells of the islets of Langerhans may contain the NOS-enzyme and thus constitutively produce nitric oxide.
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PMID:Cytochemical localization of NADPH-diaphorase in the four types of pancreatic islet cell. 752 33

The activity of reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) was examined histochemically in the rat cerebellar cortex at the light and electron microscopical level. Different staining patterns were observed depending on the technique used. Electron dense reaction product was seen on distinct membrane portions of the endoplasmic reticulum including the nuclear envelope in most of the neurons and in endothelial cells. Electron microscopically no activity staining was seen in glial cells, including Bergmann cells. The addition of the detergent Triton X-100, usually applied in the light microscopical diaphorase histochemistry, led to a striking diminution in membrane staining. In such preparations inspected electron microscopically formazan formed small granules which were evenly distributed over the cytoplasm.
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PMID:Localization of NADPH-diaphorase/nitric oxide synthase activity in the rat cerebellar cortex: a light and electron microscopical study. 753 9

The recent discovery of the identify of nitric oxide synthase with the reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) has powerfully stimulated the anatomical localization of sites of nitric oxide synthesis in the nervous system. In the present study the widely used light microscopical technique for NADPH-d staining was adapted to the electron microscopical level by applying the tetrazolium salt 2-(2'-benzothiazolyl)-5-styryl-3-(4'-phthalhydrazidyl)tetrazolium chloride (BSPT) which produces an electron-dense reaction product, BSPT-formazan. Predominantly membranes of the endoplasmic reticulum were stained. Apart from singular heavily labeled neurons, a majority of nerve cells, light microscopically "unstained", shows sporadically formazan deposits, and, likewise, but regionally different, a few astroglial cells. Lesions induced by the glutamate agonists quinolinic acid and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) display surviving neurons, which are predominantly stained for NADPH-d. Astroglial cells within lesioned areas exhibit increased amounts of reaction product, apparently as a consequence of enzyme induction.
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PMID:Nitric oxide synthase in the brain: light and electron microscopical findings based on the NADPH-diaphorase reaction. 753 22

Nicotinamide-adenine-dinucleotide phosphate-diaphorase positive cells in the chick thymus were studied at the electron-microscopic level. The formazan, a marker for the enzyme nitric oxide synthase, labelled cystic, undifferentiated, endocrine-like and myoid cells in the medulla. Some lymphoid and reticulo-epithelial cells were also lightly labelled. The reaction product was predominantly bound to the membranes of the endoplasmic reticulum in all the cells labelled and also to the nuclear envelope and outer membrane of mitochondria. The Golgi apparatus and the plasma membrane were free of the reaction product.
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PMID:Ultrastructural localisation of NADPH-diaphorase in the chick thymic medulla. 753 55

A study has been made of the distribution of nitric oxide synthase (NOS) in the developing avian ciliary ganglion. Nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) activity first appeared in ciliary neurones at embryonic day 10 (E10). The number of NADPH-d positive neurones appeared maximal at this age and thereafter declined; at post hatched day 4 (P4) these neurones were found predominately in the periphery of the ganglion. At the light microscope level the NADPH-d stain appeared throughout the cell soma of the ciliary neurones. This was confirmed using tissue culture techniques. Ultrastructural delineation of horseradish peroxidase-labelled NOS antibodies was also found in the calyx where it was bound to the membranes of the endoplasmic reticulum as well as to the outer membranes of mitochondria. This distribution of NOS in the soma and calyx is consistent with the physiological role of NO as a co-transmitter and retrograde messenger that regulates the quantal secretion of the principal transmitter, acetylcholine, from the calyx.
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PMID:Location of nitric oxide synthase in the developing avian ciliary ganglion. 753 72

The localization of reduced nicotinamide adenine dinucleotide phosphate diaphorase in the submucous plexus of duodenum, jejunum, ileum, proximal colon, distal colon and rectum in the guinea-pig was examined histochemically by light and electron microscopy. The majority of reactive submucous neurons displayed features common to either Dogiel type I or type II neurons; some were closely adherent to the outer walls of lymphatic vessels. The use of 2-(2'-benzothiazolyl)-5-styryl-3-(4'-phthalhydrazidyl) tetrazolium chloride (BSPT) at the ultrastructural level showed that nicotinamide adenine dinucleotide phosphate diaphorase is a membrane-associated protein widely distributed in the cells, including the rough endoplasmic reticulum, Golgi apparatus and synaptic vesicles in the axon terminals associated with submucous neurons. On the basis of their diaphorase reactivity or the lack of it, the submucous neuronal somata and their associated terminals were observed to form several different kinds of synaptic configurations. The present quantitative analysis showed that the frequency of reactive submucous neurons in the large intestine was significantly higher than in the small intestine. Based on the ultrastructural localization of the diaphorase reaction product in positive cells, it is speculated that nitric oxide might be synthesized within the neurons. The demonstration of different synaptic configurations in the submucous ganglia suggests that the functional interaction between submucous neurons is extremely complex. Finally, the higher frequency of diaphorase reactive submucous neurons in the large intestine than in the small intestine indicates that submucous neurons in these two gut regions may not play equivalent roles.
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PMID:Localization of NADPH-diaphorase activity in the submucous plexus of the guinea-pig intestine: light and electron microscopic studies. 764 33

The activity and distribution of reduced nico-tinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase) in the nodose ganglion of normal and vagotomized guinea-pigs were examined by light and electron microscopy. Light microscopy confirmed a remarkable increase in the number of NADPH-diaphorase-reactive neurons in the nodose ganglion following unilateral cervical vagotomy. The increase was present at 5 days but became more prominent at 10 days and was sustained until at least 30 days after vagotomy when compared with the non-lesioned side. The NADPH-diaphorase reaction product was associated with the membrane of the rough endoplasmic reticulum, Golgi apparatus, mitochondria and nucleus of the nodose neurons. In animals killed 5 days post-operation, there was no noticeable degeneration in the nodose neurons. However, at 10 days, the mitochondria in some neurons appeared swollen and vacuolated with disrupted cristae. These changes were accentuated in some nodose neurons 20 and 30 days after vagotomy but there was no evidence of cell death. All the degenerating neurons exhibited NADPH-diaphorase activity. The increase in NADPH-diaphorase activity in the neuronal somata after vagotomy suggests that the enzyme is involved in either the retrograde degeneration or the recovery of the lesioned neurons.
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PMID:NADPH-diaphorase activity in the nodose ganglion of normal and vagotomized guinea-pigs. 876 67

The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) was examined in the upper thoracic segment of the spinal cord in rat. Under the light microscope, NADPH-d positive cell bodies and fibers were readily detected in the following areas: 1) the dorsal horn; 2) the dorsolateral funiculus and lateral spinal neurons; 3) spinal autonomic region, consisting of the nucl. intermediolaterialis pars funicularis, nucl. intermediolateralis pars principalis, nucl. intercalatus spinalis and nucl. intercalatus pars paraependymalis; and 4) in the white matter lateral to the nucl. intermediolateralis pars funicularis. In the nucl. intermediolateralis pars principalis, the positive dendrites, running in bundles, were directed medially in the gray matter towards the central canal as well as laterally in the white matter towards the pia mater. The medially-directed positive dendrites fomed a subependymal plexus around the central canal. A dense bundle of NADPH-d positive fibers were also observed running longitudinally. Combined retrograde tracing with fluorogold and NADPH-d histochemistry study revealed that some of the NADPH-d positive neurons, due to their fluorescence labelling, were sympathetic preganglionic neurons that innervated the superior cervical ganglion. Under the electron microscope, the reaction products in the neurons of the nucl. intermediolateralis pars principalis were deposited in their nuclear envelope, rough endoplasmic reticulum, mitochondria and Golgi apparatus. In the neuropil, three types of synaptic configurations were observed: between NADPH-d negative axon terminals and NADPH-d positive dendrites, between NADPH-d positive axon terminals and NADPH-d negative dendrites, and between NADPH-d positive axons terminals and NADPH-d positive dendrites. These synaptic configurations suggest that the neurons are regulated by nitric oxide released from both pre- and post-synaptic elements. The sources of the NADPH-d positive axon terminals associated with the neurons remain unclear although the possibility of their being derived from supraspinal origins has to be considered. The ultrastructural demonstration of NADPH-d reaction product in the three major types of glial cells suggests that nitric oxide might be produced by these cells, but its functional significance awaits further investigation.
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PMID:Light and electron microscopic studies of the distribution of NADPH-diaphorase in the rat upper thoracic spinal cord with special reference to the spinal autonomic region. 884 31

The ultrastructural localization of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), which has been considered to be a neuronal nitric oxide synthase (NOS), was explored in the vascular endothelial cells and perivascular nerves of the cerebral arteries in the rat. In order to detect NADPH-d activity, 2-(2'-benzothiazolyl)-5-styryl-3-4-(4'-phthalhydrazidyl) tetrazolium chloride was utilized as a substrate for NADPH-d histochemistry at the electron microscopic level. In vascular endothelial cells, NADPH-d positive deposits were observed on the nuclear envelope and the endoplasmic reticulum (smooth or rough surfaced). Positive deposits were seen on distinct membrane portions of the endoplasmic recticulum (ER) in the perivascular nerves (axons), but no positive materials were observed either in the cytoplasm of the endothelial cells or in the axoplasm of the perivascular nerves. It was concluded that NOS is located on the membranes of the ER and the nuclear envelope, and that NOS may play substantial roles in the regulation of the cerebral vessels.
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PMID:The ultrastructural localization of NADPH-diaphorase in the cerebral arteries of rats. 902 50

The present study investigated the ultrastructure of neurons in the caudal spinal trigeminal nucleus. These neurons which are believed to function as interneurons in the transmission of orofacial nonreflexive nociceptive information, measured 20 microns x 11 microns, and were nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) positive. The reaction product, formazan, was localized in the nuclear envelope, mitochondria, rough endoplasmic reticulum, and multivesicular bodies of these neurons. It was also localized in the membrane of the smooth endoplasmic reticulum at the axon terminal. The neurons were contacted by both axosomatic and axodendritic synapses formed by both NADPH-d positive and NADPH-d negative axon terminals. Two types of NADPH-d positive axon terminals could be recognized. The first was a large terminal containing many stained mitochondria and unstained small round agranular vesicles mixed with some slightly flattened ones. It formed asymmetrical axodendritic synapse. The second type of axon terminals contained pleomorphic synaptic vesicles and formed asymmetrical synapses upon both dendrites and soma. The sources of NADPH-d positive axon terminals were discussed. Most of the unstained axon terminals forming axosomatic and axodendritic synapses with stained cell bodies and dendrites contained flattened vesicles. In addition to the above, complicated synaptic configurations showing NADPH-d positive axoaxonic synapses in relation to NADPH-d negative dendritic spines were also seen in which a NADPH-d negative dendritic spine was completely contacted by a NADPH-d positive bouton which was in turn contacted by another NADPH-d positive bouton.
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PMID:Ultrastructural study of NADPH-d positive neurons in laminae I and II of the rat caudal spinal trigeminal nucleus. 939 13


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