Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.6.99.1 (NADPH-diaphorase)
 3,903 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nitric oxide and estrogen have been shown to play a critical role in the control of female reproductive function. In order to determine an anatomical relationship between nitric oxide generating neurons and estrogen target neurons, NADPH-diaphorase histochemistry was combined with estrogen receptor immunohistochemistry in the female medial preoptic area. While only a few weakly stained neurons for NADPH-diaphorase were found in ovariectomized control rats, a drastic increase in NADPH-diaphorase activity was observed in the medial preoptic nucleus of estradiol-treated ovariectomized animals. The total number of NADPH-diaphorase neurons in the estradiol-treated group increased three-fold relative to controls, and more than 80% of those neurons contained estrogen receptor-immunoreactivity in their nuclei. Since neuronal NADPH-diaphorase is nitric oxide synthase, the present result suggests that nitric oxide synthase activity can be positively regulated by estradiol in neurons containing estrogen receptor in the female medial preoptic nucleus.
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PMID:Estrogenic induction of NADPH-diaphorase activity in the preoptic neurons containing estrogen receptor immunoreactivity in the female rat. 789 61

NADPH-diaphorase (NADPH-d) histochemistry was combined with estrogen receptor (ER) immunohistochemistry in order to study effect of estrogen on NADPH-d activity and establish an anatomical relationship between NADPH-d and ER-immunoreactivity (ir) containing neurons in the ventromedial hypothalamic nucleus (VMN). Gonadectomized female and male rats received either oil (control group) or 10 micrograms of estradiol benzoate (EB) for two successive days and were sacrificed on day 4. While NADPH-d histochemistry stained a specific subpopulation of neurons in the ventrolateral portion of the VMN of all groups, there was a marked sex difference in the effect of EB treatment. EB elevated the number of NADPH-d positive neurons in females but had no significant effect in males. Double-labeling histochemistry revealed that more than 70% of the NADPH-d positive neurons contained ER-ir in the VMN of all groups, with EB-treated females having a significantly higher frequency than all other groups. Since neuronal NADPH-d is nitric oxide synthase (NOS), these results provide anatomical evidence for an association of estrogen with NOS in the rat VMN and suggest that NOS activity can be modulated by estradiol in estrogen sensitive neurons.
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PMID:Colocalization of NADPH-diaphorase and estrogen receptor immunoreactivity in the rat ventromedial hypothalamic nucleus: stimulatory effect of estrogen on NADPH-diaphorase activity. 792 35

Candida albicans, the most common fungal pathogen of humans, possesses an estrogen-binding protein (EBP) that binds mammalian estrogens with high affinity. We report here the cloning and complete nucleotide sequence of a gene encoding a C. albicans EBP. Amino acid sequences obtained from cyanogen bromide fragments of purified EBP were used to design oligonucleotide primers for PCR. An 800-bp product was amplified and used to screen a C. albicans genomic library. A clone was isolated containing an insert with an open reading frame of 1221 nt capable of encoding a protein with 407 amino acids and having a calculated molecular mass of 46,073 Da, the estimated size of EBP. The cloned gene, expressed in Escherichia coli as a lacZ fusion protein, demonstrated high-affinity binding for estradiol and a competition profile comparable to C. albicans wild-type EBP. Northern blots of C. albicans RNA revealed a single transcript of approximately 1600 nt, whereas Southern blots identified three hybridizing fragments. Computer searches of data bases showed that EBP shares a 46% amino acid identity with the old yellow enzyme, an oxidoreductase from Saccharomyces cerevisiae, but was unrelated to the human estrogen receptor as previously speculated. In addition, a 51-amino acid region of EBP is highly conserved among a group of flavoproteins including old yellow enzyme. Expressed EBP was shown to exhibit oxidoreductase activity that could be inhibited by 17 beta-estradiol in vitro. In conclusion, the EBP from C. albicans has no evident homology to the mammalian steroid receptor superfamily but appears to be a member of a recently identified family of flavoproteins.
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PMID:Candida albicans estrogen-binding protein gene encodes an oxidoreductase that is inhibited by estradiol. 830 68

The distribution of the enzymes NADPH diaphorase and nitric oxide synthase in the ventromedial nucleus of the hypothalamus of cycling and ovariectomized/estrogen-treated and control female rats was demonstrated using histochemical and immunocytochemical methods. Serial section analysis of vibratome sections through the entire ventromedial nucleus showed that NADPH diaphorase cellular staining was localized primarily in the ventrolateral subdivision. NADPH diaphorase staining was visible in both neuronal perikarya and processes. Light microscopic immunocytochemistry using affinity-purified polyclonal antibodies to brain nitric oxide synthase revealed a similar pattern of labelling within the ventromedial nucleus and within neurons of the ventrolateral subdivision of the ventromedial nucleus. Control experiments involved omitting the primary antibodies; no labelling was visible under these conditions. Some, but not all, neurons in the ventrolateral subdivision of the ventromedial nucleus contained both NADPH diaphorase and brain nitric oxide synthase as demonstrated by co-localization of these two enzymes in individual cells of this area. That NADPH diaphorase and brain nitric oxide synthase were found in estrogen-binding cells was shown by co-localization of NADPH diaphorase and estrogen receptor and brain nitric oxide synthase and estrogen receptor at the light and ultrastructural levels, respectively. Our studies suggest that brain nitric oxide synthase is present and may be subject to estrogenic influences in lordosis-relevant neurons in the ventrolateral subdivision of the ventromedial nucleus. The hypothalamus is a primary subcortical regulatory center controlling sympathetic function. Therefore, not only is nitric oxide likely to be important for reproductive behavior, but also for the regulation of responses to emotional stress and other autonomic functions.
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PMID:NADPH diaphorase activity and nitric oxide synthase immunoreactivity in lordosis-relevant neurons of the ventromedial hypothalamus. 897 27

Based on previous studies demonstrating that reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase (ND) activity is modulated by estradiol and the discovery of a new subtype of estrogen receptor highly expressed in the paraventricular nucleus of the hypothalamus (PVN), a possible estrogen influence on this activity was investigated in the neuronal populations (magno- and parvicellular) of this nucleus. Cryostat sections were cut and processed for the histochemical detection of the ND activity. Following ovariectomy (14 days), numerical data displayed a slight decrease in the number of ND-neurons, especially in the posterior magnocellular and the medial parvicellular subdivisions, which was reversed after daily treatment with estradiol benzoate. Administration of estradiol benzoate to male rats (14 days) induced a significant increase (P < 0.05) in the number of ND-neurons, mainly at the level of the posterior magnocellular subdivision. These data indicate that paraventricular ND-neurons are influenced by estradiol.
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PMID:Reduced nicotinamide adenine dinucleotide phosphate-diaphorase activity in the paraventricular nucleus of the rat hypothalamus is modulated by estradiol. 977 53