Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:1.6.99.1 (NADPH-diaphorase)
3,903 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The three isoforms of nitric oxide synthase (NOS), neuronal (nNOS), endothelial (eNOS), and inducible (iNOS), can be visualized in cells and tissues by NADPH-diaphorase (NADPH-d) histochemistry, immunocytochemistry and in situ hybridization. Histochemical demonstration of NADPH-d shows the formazan final reaction product as a solid blue deposit. The ultrastructural localization of NADPH-d in the rat hippocampus showed an electron-dense deposit on membranes predominantly of the endoplasmic reticulum. The immunohistochemical demonstration of nNOS, using the nickel enhancement technique, shows positive reaction product over the dendrites and the soma of the nerve cell in the rat brain. Ultrastructural localization of nNOS in whole mount preparations of myenteric plexus and circular smooth muscle from guinea-pig ileum shows that NOS immunoreactivity was patchily distributed in myenteric neurones and was not specifically associated with any intracellular organelles or with plasma membranes. In situ hybridization, using radio-labelled probes, was used to study nNOS mRNA in lumbar dorsal root ganglia after peripheral transection of the sciatic nerve in rats. Labelling of the NOS mRNA-positive neurones is observed as a series of dense granules over the entire cell. NADPH-d histochemistry, immunocytochemistry and in situ hybridization each have a significant role to play in the localization of NOS. NADPH-d detects an enzyme associated with the NOS molecule, immunocytochemistry detects the NOS molecule, and in situ hybridization detects mRNA for NOS. Therefore, if each of these techniques is applied in carefully controlled experiments, consideration of the accumulated data should be valuable in revealing insights into the biology of NOS.
...
PMID:Histochemical methods for detecting nitric oxide synthase. 857 39

NADPH-diaphorase (NADPH-D) activity and immunoreactivity for neural and endothelial nitric oxide synthase (nNOS and eNOS, respectively) were used to investigate nitric oxide (NO) regulation of penile vasculature. Both the histochemical and immunohistochemical techniques for NOS showed that all smooth muscles regions of the penis (dorsal penile artery and vein, deep penile vessels, and cavernosal muscles) were richly innervated. The endothelium of penile arteries, deep dorsal penile vein, and select veins in the crura and shaft were also stained for NADPH-D and eNOS. However, the endothelium of cavernous sinuses was unstained by both techniques. Fewer fibers were seen in the glans penis, those present being associated with small blood vessels and large nerve bundles near the trabecular walls. All penile neurons in the pelvic plexus, located by retrograde transport of a dye placed in the corpora cavernosa penis, were stained by the NADPH-D method. Essentially similar results were obtained with an antibody to nNOS. These data suggest that penile parasympathetic neurons comprise a uniform population, as all seem capable of forming nitric oxide. However, in contrast to the endothelium of penile vessels, the endothelium lining the cavernosal spaces may not be capable of nitric oxide synthesis.
...
PMID:Neural and endothelial nitric oxide synthase activity in rat penile erectile tissue. 858 13

The trophoblast invasion of uteroplacental arteries in the guinea pig has been studied by means of electron microscopy and immunohistochemisty. To identify trophoblast cells, smooth muscle cells, and endothelial cells, antibodies against cytokeratins, smooth muscle myosin, desmin, and vimentin were employed. Furthermore, the immunohistochemical expression patterns of nitric oxide synthase isoforms (eNOS, mNOS and bNOS) were studied and were compared with the enzyme histochemical staining for NADPH-diaphorase. Dilation of uteroplacental arteries begins prior to day 30, when trophoblast cells that coexpress endothelial and macrophage nitric oxide synthase can be found in the vicinity of the vessels and replace the surrounding peritoneal mesothelium. Trophoblast invasion of the arterial walls and the subsequent wall destruction are only secondary effects. Starting around day 50, the final steps of pregnancy-dependent vessel modifications involve intraarterial trophoblast adhesion to the endothelium and subsequent replacement of the endothelium by the trophoblast cells. These may centrifugally invade the vessel media eventually forming intraluminal plugs. These findings led us to the conclusion that in the guinea pig pregnancy-induced physiological dilation of the uteroplacental arteries is due to the effect of nitric oxide rather than being caused by trophoblast-induced media destruction.
...
PMID:Physiological dilation of uteroplacental arteries in the guinea pig depends on nitric oxide synthase activity of extravillous trophoblast. 858 35

This study focused on two points concerning the histochemical and immunohistochemical detection of neurons that produce nitric oxide (NO): (a) the effect of fixation and other methodological parameters on the staining pattern of both NADPH-diaphorase (NADPH-d) histochemistry and nitric oxide synthase (NOS) immunohistochemistry, and (b) the possibility that neurons display immunoreactivity against NOS antisera obtained from non-neuronal sources. Frontal sections of rat brains, fixed with 4% paraformaldehyde according to different protocols, were processed for single and double labeling using NADPH-d histochemistry and neuronal (nNOS), macrophagic (macNOS), and endothelial (eNOS) NOS immunohistochemistry. Our results show that variations in the fixative schedule, even within standard parameters, produce qualitative and quantitative changes in NADPH-d labeling. The effect of fixative on weakly stained neurons is different from that on heavily stained neurons. In subfixed brains, a large number of NOS-positive neurons lose their NADPH-d activity, whereas NOS immunolabeling remains unaltered. This finding may be particularly interesting in morphological studies that compare NADPH-d activity under experimental conditions that can affect brain perfusion. On the other hand, many cortical and subcortical neurons show macNOS immunoreactivity, most of it colocalized with nNOS.
...
PMID:Histochemical and immunohistochemical detection of neurons that produce nitric oxide: effect of different fixative parameters and immunoreactivity against non-neuronal NOS antisera. 898 32

Nitric oxide (NO) is suggested as an important mediator for the regulation of biological processes. In the present study we tried to determine histochemically and immunohistochemically the localization and distribution of the constitutive NO-synthase Isoforms (bNOS and eNOS) of 14 normal non-obstructive and 12 hyperplastic obstructive human prostates. Differentiated nitrinergic innervation was shown for the prostate glands, fibromuscular stroma and blood vessels by NADPH-diaphorase staining and immunohistochemically with specific NOS antibodies. In the specimens with benign prostatic hyperplasia nitrinergic innervation seems to be distinctly reduced. The vascular distribution of NOS provides evidence for segmental differentiation of NO-mediated vascular regulation. The NADPH-diaphorase reaction was not confirmed immunohistochemically by the specific NOS antibody in the glandular epithelium. The distribution of NO synthase shows the importance of nitric oxide in the regulation of smooth muscle tone, blood flow and secretory function in the normal and hyperplastic human prostate.
...
PMID:[Pattern of distribution of constitutive isoforms of NO synthase in the normal prostate and obstructive prostatic hyperplasia]. 934 Aug 96

Previous studies have shown that nitric oxide synthase (NOS), the enzyme that catalyzes the formation of nitric oxide (NO), is expressed in skeletal muscle. The aim of the present study was to test the hypothesis that NO can modulate glucose metabolism in slow- and fast-twitch skeletal muscles. Calcium-dependent NOS was detected in skeletal muscle, and the enzyme activity was greater in fast-type extensor digitorum longus (EDL) muscles than in slow-type soleus muscles. Both the neuronal-type (nNOS) and endothelial-type (eNOS) enzymes are expressed in resting skeletal muscles. However, nNOS protein was only detected in EDL muscles, whereas eNOS protein contents were comparable in soleus and EDL muscles. NOS expression in muscle cryosections (diaphorase histochemistry) was located in vascular endothelium and in muscle fibers, and the staining was greater in type IIb than in type I and IIa fibers. The macrophage-type inducible NOS (iNOS) was not detected in resting muscle, but endotoxin treatment induced its expression, concomitant with elevated NO production. iNOS induction was associated with impaired insulin-stimulated glucose uptake in isolated rat muscles. In vitro, NOS blockade with specific inhibitors did not affect basal or insulin-stimulated glucose transport in EDL or soleus muscles. In contrast, the NO donors GEA 5024 and sodium nitroprusside induced dose-dependent inhibition (up to 50%) of maximal insulin-stimulated glucose transport in both muscles with minor effects on basal uptake values. GEA 5024 also blunted insulin-stimulated glucose transport and amino acid uptake in cultured L6 muscle cells without affecting insulin binding to its receptor. On the other hand, the permeable cGMP analogue dibutyryl cGMP did not affect muscle glucose transport. These results strongly suggest that NO modulates insulin action in both slow- and fast-type skeletal muscles. This novel autocrine action of NO in muscle appears to be mediated by cGMP-independent pathways.
...
PMID:Expression of nitric oxide synthase in skeletal muscle: a novel role for nitric oxide as a modulator of insulin action. 935 14

Nitric oxide (NO) is an important mediator in the relaxation of cavernosal smooth muscle. The present study examines the existence and location of the constitutive isoform eNOS (endothelial NO synthase) accompanying the already substantiated neurogenic NOS (nNOS) in the human corpus cavernosum of men with and without erectile dysfunction. Activities of NOS enzymes were examined in specimens of 11 potent and nine long-term impotent patients by means of light and electron microscopy using NADPH-diaphorase staining and immunohistochemical eNOS-specific, smooth muscle actin-specific and nNOS-specific markers. Cavernosal smooth muscle shows a distinct expression of eNOS. In contrast to the weaker expression of eNOS and nitrinergic innervation found in larger veins, the small intracavernosal helicine arteries express large quantities of eNOS and possess a dense nitrinergic innervation. Long-term impotent patients display a broad heterogeneity in eNOS expression and nitrinergic innervation while no overall correlation between NOS expression and erectile function was observed. The expression of eNOS indicates eNOS as a main source of NO alongside nNOS. The differentiated localization of eNOS supports at least a role of this isoform in vascular regulation.
...
PMID:Evidence for the involvement of endothelial nitric oxide synthase from smooth muscle cells in the erectile function of the human corpus cavernosum. 963 46

To provide information concerning a possible biologic role of nitric oxide (NO) in smoking-related emphysema, we performed immunohistochemical studies in lung tissue from control subjects and patients with mild and severe emphysema. We studied the presence of inducible and endothelial NO synthases (iNOS and eNOS, respectively) and determined nicotinamide diphosphate (NADPH) diaphorase activity. Patients with severe emphysema showed lower percentages of iNOS- and eNOS-positive alveolar macrophages in situ than did patients with mild emphysema. In patients with both iNOS and eNOS immunoreactivity in macrophages, the majority of the macrophages expressed either iNOS or eNOS, whereas only a minority of the macrophages showed iNOS and eNOS immunoreactivity simultaneously. Immunoreactivity for eNOS in endothelial and/or bronchiolar epithelial cells and NADPH diaphorase activity in macrophages and in endothelial, epithelial, and smooth muscle cells were similar in the three studied groups. The expression of eNOS in macrophages suggests that eNOS plays an additional role, besides iNOS, in the NO housekeeping in inflammatory processes in pulmonary tissue. We suggest that NO might have a protective role in maintenance of structural integrity of pulmonary tissue after smoke-induced damage.
...
PMID:Macrophages in lung tissue from patients with pulmonary emphysema express both inducible and endothelial nitric oxide synthase. 968 86

We had previously shown NADPH diaphorase activity in fixed tissue slices of the insular cortex of the Syrian golden hamster (Mesocricetus auratus). The objective of this work was to determine the chemical identity of agents responsible for the observed NADPH diaphorase activities. Three different enzymatic NADPH diaphorase activities were distinguished in the insular cortex. (a) The activity seen in endothelial cells was not characterized histochemically, but it co-localized with eNOS-like immunoreactivity. (b) The neuronal Type I activity showed little sensitivity to 10(-5) M dicoumarol, could use either alpha- or beta-NADPH with almost equal facility, and co-localized with nNOS-like immunoreactivity. This activity was primarily attributable to nNOS. (c) The neuronal Type II activity was greatly attenuated by 10(-5) M dicoumarol, had a strong preference for beta-NADPH (rather than alpha-NADPH), and did not co-localize with any NOS-like immunoreactivity. These characteristics also apply to the NADPH diaphorase activity observed in the diffuse blue band in Layers II and III of agranular and dysgranular insular cortex and in the meshwork of cortical fibers. This staining was due primarily to a dicoumarol-sensitive dehydrogenase(s), either an isozyme of DT diaphorase (EC 1.6.99.2), or NADPH dehydrogenase (quinone) (EC 1.6. 99.6), or to a novel dicoumarol-sensitive NADPH dehydrogenase.
...
PMID:NOS- and non-NOS NADPH diaphorases in the insular cortex of the Syrian golden hamster. 988 55

We have produced a digital atlas of the distribution of nitric oxide synthase (NOS) in the mouse brain as a reference source for our studies on the roles of nitric oxide in brain development and plasticity. NOS was labeled using nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry. In addition, choline acetyltransferase (ChAT) immunocytochemistry was used to identify cholinergic cells because many of the NADPHd positive cells were thought to colocalize acetylcholine. Some sections were also labeled with antibodies to either the neuronal (nNOS) or endothelial (eNOS) isoforms of NOS. Series of sections from 11 C57/BL6 mice were collected and labeled for NADPHd and/or ChAT. We collected two types of data from this material: color digital photographs illustrating the density of cell and fiber labeling, and computer/microscope plots of the locations of all the labeled cells in selected sections. The data can be viewed as either a series of single-section maps produced by combining the plots with the digital images, or as 3-D views derived from the cell plots. The atlas of labeled cell maps, together with selected color photographs and 3-D views, is available for viewing via the World Wide Web (http:@nadph.anatomy.lsumc.edu). Examination of the atlas data has revealed several points about the distribution of NOS throughout the mouse brain. Firstly, different populations of NADPHd-positive neurons can be distinguished by different patterns of staining. In some brain areas neurons are intensely stained by the NADPHd technique where label fills the cell bodies and much of the dendritic trees. In other brain regions labeling is much lighter, is principally confined to the cytoplasm of the cell soma, and extends only a short distance within proximal dendrites. Intense labeling is typical of neurons in the caudate/putamen and mesopontine tegmental nuclei. Most of the labeled neurons in the cortex also stain this way. Lighter, "granular" label is found in many other nuclei, including the medial septum, hippocampus, and cerebellum. In addition to staining pattern, we have also noted that different subpopulations of NOS-neurons can be distinguished on the basis of colocalization with ChAT. Substantial overlap of the distributions of these two substances was observed although very little colocalization was found in most cholinergic cell groups except the mesopontine tegmental nuclei. Other points of interest arising from this project include the apparent lack of NADPHd labeling in the CA1 pyramidal cells of the hippocampus or the Purkinje neurons in the cerebellum. This observation is especially relevant given that synaptic plasticity in these regions is reported to be nitric-oxide dependent.
...
PMID:A web-accessible digital atlas of the distribution of nitric oxide synthase in the mouse brain. 993 33


1 2 3 4 5 Next >>

---