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:1.3.5.1 (
succinate dehydrogenase
)
8,177
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effect of a single dose of 5 mg/kg body weight of aflatoxin B1 on rat liver mitochondrial enzymes,
succinate dehydrogenase
(
SDH
) and Mg++ adenosine triphosphatase (Mg++-ATPase) and on certain lipids were studies at various intervals of time from 3 to 24 hours. A significant decrease in the specific activity of
SDH
was observed after 6, 12, 18 and 24 hr treatment. The Mg++-ATPase activity remained unaffected up to 12 hr but appreciably decreased after, 18 and 24 hr of the treatment. The level of phospholipids and cholesterol were not altered after 3, 6 and 12 hr treatment, thereafter (18 and 24 hr) an increase was observed in both the lipids following the aflatoxin treatment. Medroxyprogesterone acetate (MPA) did not cause any alteration in the specific activities of these enzymes as well as levels of cholesterol and phospholipids. The treatment with MPA caused significant increase in contents of cytochromes P-450, b5 and activities of Arylhydrocarbon hydroxylase (AHH), UDP-glucuronyl transferase (UDP-GT) and
NADPH
-cytochrome C-reductase of hepatic microsomes. It was observed that pretreatment with medroxyprogesterone acetate (MPA) could significantly minimuze the depression caused in mitochondrial
SDH
and Mg++-ATPase activities by aflatoxin B1.
...
PMID:Modification of aflatoxin B1-induced changes in certain mitochondrial enzymes and lipids by medroxyprogesterone acetate. 294 74
Two different fractions were present in crystalline bovine liver catalase, and could be resolved using dye-ligand affinity chromatography with Red-A Matrex gel containing Procion HE 3B. The major part (alpha) was not adsorbed on this gel. The second fraction (beta) was firmly adsorbed to the gel, and could be eluted either by high salt or by
NADPH
in the micromolar range. Elution of catalase beta was also obtained with NADH, NADP+, and ADP at higher concentration. Fractions alpha and beta displayed no detectable difference in specific activity, stability to heat, and light absorption data. It is suggested that the difference in behavior between alpha and beta is related to the binding of
NADPH
to the mammalian catalase [H. N. Kirkman and G. F. Gaetani (1984) Proc. Natl. Acad. Sci. USA 81, 4343-4347], and that the beta fraction corresponds to the enzyme molecules that have at least one free site for
NADPH
binding. Modifications of catalase molecules in the presence of dithioerythritol (DTE) were examined using light absorption and EPR data. Thiol induced changes that corresponded to the formation of catalase
complex II
. They were partially reversed by
NADPH
at very low level, and the dinucleotide appeared to be oxidized in this process. DTE-treated bovine catalase was totally adsorbed on the Red-A Matrex columns, and could be eluted as fraction beta. Similar spectral changes in the presence of DTE and
NADPH
were displayed by a bacterial catalase from Proteus mirabilis. This enzyme was also able to oxidize
NADPH
, but was not adsorbed by Red-A Matrex. This work suggests that dye-affinity chromatography provides a very convenient tool for isolating dinucleotide-depleted catalase from bovine liver, facilitating further study of the physiological function of this cofactor within the enzyme.
...
PMID:Interaction between pyridine adenine dinucleotides and bovine liver catalase: a chromatographic and spectral study. 301 30
The damaging effects of ADP/Fe/
NADPH
-induced lipid peroxidation were studied on the enzymes and membranes of rat liver mitochondria. Succinate, an inhibitor of mitochondrial lipid peroxidation, prevented or delayed most of the damage caused by the peroxidation on different mitochondrial structures and functions. There were marked abnormalities on the electrophoretic pattern of mitochondrial proteins during the course of lipid peroxidation. The disappearance of particular polypeptide bands and the accumulation of high-molecular-weight aggregates could be observed. Succinate was found to delay these effects. As a consequence of lipid peroxidation the succinate oxidase activity of mitochondria was decreased. The
succinate dehydrogenase
enzyme and the component(s) of the respiratory chain were inactivated. Succinate prevented the inactivation of
succinate dehydrogenase
but did not protect the other components of terminal oxidation chain. From the matrix enzymes the glutamate dehydrogenase retained its full activity but the NADP-linked isocitrate dehydrogenase was inactivated. The mitochondrial membranes became permeable to large protein molecules. Succinate prevented the inactivation of isocitrate dehydrogenase and delayed the release of protein molecules from mitochondria.
...
PMID:Effect of succinate on mitochondrial lipid peroxidation. 2. The protective effect of succinate against functional and structural changes induced by lipid peroxidation. 303 29
Within the uterine glands, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH,
NADPH
), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase,
succinate dehydrogenase
, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the activities of G-6-PDH, 6-PGDH, and cytochrome oxidase increase within secreting cells during the 2nd half of pregnancy. The activities of the other enzymes remained almost unchanged during the period of investigation. The description of our results distinguishes between gland neck, middle, and distal part of the secretory unit, respectively. In general, the enzyme activities are similar within the middle and distal gland segments, but lower in the epithelia of the neck region. The activity of dehydrogenases was medium to intensive within the middle and distal gland segments, but only low to medium within the neck portion. Of the hydrolases, the acid phosphatase, ATPase, leucine aminopeptidase, and beta-galactosidase demonstrated an intensive activity within activity secreting cells. The enzyme activities of the gland epithelia are compared with these of the uterine surface epithelia and the histochemical results are discussed in context with their significance in histiotrophic nutrition.
...
PMID:[Enzyme histochemistry of the pig placenta. III. Histotopics of enzymes in the uterine epithelium]. 309 49
Supermitochondrial liquid (SL) of rat and guinea-pig liver increases the activity of 2, 3, 5 triphenyltetrasolium chloride (TPC) and tetrasolium violet (TV) reduction at succinate, NADH and
NADPH
oxidation by mitochondria (MC). SL contains an activating factor A, being evidently of a protein nature and factor B, increasing the activating activity of factor A. NAD, NADP, NADH and NADP at 5 x 10(-5)-1 x 10(-4) M concentration activate the TPC and TV reduction at succinate oxidation by mitochondria. TPC and TV reduction at succinate and NADP oxidation by mitochondria makes antimicin and cyanide sensitive. SL does not influence
succinate dehydrogenase
activity, when used as electron acceptors of ferricyanide, blue Vurster, cytochrome C, blue and violet nitrotetrasolium. Activation of electron transfer chair between cytochrome C and oxygen is supposed to be responsible for such an effect.
...
PMID:[Activation of electron transport at the terminal site of the respiratory chain by the submitochondrial fluid from the rat and guinea pig liver]. 320 64
A method has been developed for the histochemical demonstration of a variety of dehydrogenases in freeze-dried or fixed resin-embedded tissue. Seven dehydrogenases were studied. Lactate dehydrogenase, NADH dehydrogenase and
NADPH
tetrazolium reductase were all demonstrable in sections of paraformaldehyde-fixed resin-embedded tissue. Freeze-dried specimens were embedded, without fixation, in glycol methacrylate resin or LR Gold resin at either 4 degrees C or -20 degrees C. All the dehydrogenases except
succinate dehydrogenase
retained their activity in freeze-dried, resin-embedded tissue. Enzyme activity was maximally preserved by embedding the freeze-dried tissue specimens in glycol methacrylate resin at -20 degrees C. The dehydrogenases were accurately localized without any diffusion when the tissue sections were incubated in aqueous media. Addition of a colloid stabilizer to the incubating medium was not required. Freeze-drying combined with low-temperature resin embedding permits accurate enzyme localization without diffusion, maintenance of enzyme activity and excellent tissue morphology.
...
PMID:Dehydrogenase enzyme histochemistry on freeze-dried or fixed resin-embedded tissue. 324 Sep 50
Histochemical assays, hormonal quantitation, and steroid biosynthetic studies were carried out with adrenal glands obtained from four stranded whales of two different species (Kogia breviceps and Mesoplodon europaeus), and selected comparisons were made with the results of similar studies of adrenals from terrestrial mammals (man, beef, rat). Histochemical chemical assays of the whale glands for
succinic dehydrogenase
activity (SDA) showed an intense SDA-positive reaction in the peripheral cortex, and an SDA-negative central medulla, a pattern similar to that found in terrestrial mammals; the whale adrenals, however, demonstrated a markedly pseudolobulated appearance because of a festooned corticomedullary junction. On radioimmunoassay of preformed cortical steroid hormones, corticosterone (B) exceeded cortisol (F) levels by a factor of 3 in the whale adrenals and aldosterone (Aldo) concentrations were 20-100 times lower than in the terrestrial mammals studied. HPLC determinations of preformed medullary catecholamines showed that, contrary to the findings in the terrestrial mammals studied, norepinephrine predominated over epinephrine and the levels of dopamine were much higher in the whale adrenals. In vitro, surviving sections of whale adrenals elaborated B from endogenous substrates, but not F or Aldo. Incubations of subcellular fractions of the whale adrenals with 14C-labeled precursors resulted in the isolation of several steroid intermediates (pregnenolone, progesterone, deoxycorticosterone) as well as the glucocorticoid end-product B, but again without evidence of the formation of either F or Aldo. In keeping with studies in terrestrial mammals, the enzymatic reactions involved in the conversion of [14C]cholesterol to B occurred under aerobic conditions, required the presence of an exogenous
NADPH
-generating system, and had identical subcellular localization in the whale adrenals. The process of steroid biosynthesis thus appears generally similar in aquatic and terrestrial mammals. It is possible that some of the unusual findings in the whale adrenals studies here may be related to the profound stress of stranding experienced by these marine mammals.
...
PMID:The adrenal gland of stranded whales (Kogia breviceps and Mesoplodon europaeus): morphology, hormonal contents, and biosynthesis of corticosteroids. 342 60
The degree of mitochondrial ADP/Fe/
NADPH
-induced lipid peroxidation was increased up to the fourth day after 9.0 Gy whole body gamma-irradiation. The lipid peroxidation inhibiting effect of succinate added to isolated mitochondria was diminished as a consequence of irradiation. The succinate, administered in vivo prior to irradiation, decreased the amount of malondialdehyde production and protected the
succinate dehydrogenase
enzyme against inactivation. The mean survival of succinate-pretreated animals was much longer than that of controls. The role of mitochondrial lipid peroxidation in the pathogenesis of radiation injury is discussed.
...
PMID:The inhibitory effect of succinate on radiation-enhanced mitochondrial lipid peroxidation. 349 7
In porcine areolar placental epithelia, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetyl-hexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, nonspecific esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH,
NADPH
), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase,
succinate dehydrogenase
, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that the enzyme activities remained almost unchanged during the period of investigation. Of the dehydrogenases, the diaphorases as well as succinate and lactate dehydrogenase demonstrated generally an intensive activity within the epithelia. The activity of the other dehydrogenases was only low. The activity of unspecific esterase was very intensive within the uterine epithelia but remarkably low within chorionic epithelia. Contrarily, the reaction of adenosine triphosphatase was more intensive within chorionic than uterine epithelia. All investigated glucosidases reacted distinctly positive within chorionic epithelia, but only beta-N-acetyl-hexosaminidase and beta-galactosidase in uterine epithelia. The high activity of acid phosphatase, especially within the chorionic epithelium, seems to be connected with uteroferrin, an iron-binding protein. The histochemical results are discussed in context with the function of the areolae in histiotrophic nutrition and iron transport.
...
PMID:[Enzyme-histochemical studies of the pig placenta. II. Histotopics of enzymes in the areolar placenta epithelium]. 392 41
Histochemical investigation of altered dehydrogenase enzyme activity in putative pre-neoplastic lesions induced by N-ethyl-N-hydroxyethylnitrosamine in the rat liver revealed a clear increase in
NADPH
-generating potential, most markedly within nodules. Glucose-6-phosphate dehydrogenase, malic enzyme and isocitrate dehydrogenase all showed elevated activity while the activities of
succinate dehydrogenase
and beta-hydroxybutyrate dehydrogenase were reduced. Alteration in enzyme activity suggested an adaptive shift in metabolism, the increase in levels of enzymes responsible for generation of reduced NADP possibly conferring enhanced drug detoxifying or cholesterogenic potential.
...
PMID:Dehydrogenase histochemistry of N-ethyl-N-hydroxyethylnitrosamine-induced focal liver lesions in the rat--increase in NADPH-generating capacity. 394 19
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>