Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The histopathological status and histologically demonstratable succinate dehydrogenase activity were evaluated on contiguous heart sections of rats fed low erucic acid rapeseed oil for 18 weeks. The histologically demonstratable SDH activity was quantified and could be related with the severity of the lesion at the same location. These results were discussed in terms of effects of dietary fat on mitochondria.
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PMID:Succinate dehydrogenase activity in relation with cardiac morphology in rats fed low erucic acid rapeseed oil. 653 36

The relative efficiencies of phenazine methosulfate (PMS), 1-methoxy-phenazine methosulfate (MPMS) and Meldola Blue (MB) as electron carriers were determined biochemically (non-enzymic NADH-tetrazolium salt-test) and by quantitative histochemistry (heart and kidney slices; succinate dehydrogenase, SDH; lactate dehydrogenase, LDH). MPMS developed the highest electron transfer velocity in biochemical assays. The reaction was independent of the pH value between 7.0-8.5. PMS and MB always showed a lower transfer ability in biochemical tests which was higher with iodonitrotetrazolium chloride (INT) than with nitro blue tetrazolium chloride (NBT). A distinct pH dependence was demonstrable with MB in this respect, preferentially using INT as tetrazolium salt. Quantitative histochemical results with electron carriers are often at variance with biochemical ones. MPMS leads to somewhat higher demonstrable activities only in the determination of the NAD-dependent LDH, whereas MB results in somewhat higher LDH activity than PMS (reaction medium with agarose). MB and PMS yielded almost equally high activities in the demonstration of the flavoprotein-dependent SDH using a reaction medium with agarose. With an aqueous reaction medium, PMS resulted in higher SDH activities than MB. MPMS always had the lowest efficiency in electron transfer ability using an aqueous or agarose containing reaction medium (SDH). With PVA in the reaction medium (SDH determination) PMS was clearly superior to MPMS. MB showed only a small transfer activity under these conditions because PVA seems to bind MB almost completely. It is concluded that in histochemistry an appropriate electron carrier and electron carrier concentration must be determined for different incubation conditions, tissues, tissue preparations and dehydrogenases studied. General statements about the efficiency or inefficiency of an electron carrier as a result of only one incubation condition does not seem to be justified.
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PMID:Quantitative dehydrogenase histochemistry with exogenous electron carriers (PMS, MPMS, MB). 711 85

This study investigated the hypothesis that the adaptations in skeletal muscle to prolonged exercise overload, involving high levels of adenosine triphosphate (ATP) resynthesis, result in a preferential adaptation to pathways involved in energy metabolism. The change in selected properties of skeletal muscle during a period of reduced activity was used as an indication of training-induced adaptations. Muscle biopsy samples from the vastus lateralis were analyzed 6 weeks and 18 weeks after a 5-month, intense, intermittent training program. Significant reductions occurred (p less than 0.05) in enzyme activities representative of the citric acid cycle (succinic dehydrogenase, SDH), beta oxidation of free fatty acids (3-hydroxyacyl CoA dehydrogenase, HADH), glycogenolysis (total phosphorylase, PHOSP), and glycolysis (phosphofructokinase, PFK). In addition, reductions in concentration (p less than 0.05) were also found for ATP, creatine phosphate (CP), and glycogen. With the exception of PFK, all enzyme changes and the high energy phosphates reached new stable levels by at least the 6th week of detraining. The absence of changes in muscle cell type and size during the detraining period supports the hypothesis that adaptations in energy potential of the muscle cell predominate in this type of high intensity overload situation.
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PMID:Biochemical and histochemical alterations in skeletal muscle in man during a period of reduced activity. 721 1

Thermal inactivation of hepatic succinic dehydrogenase (SH) (EC 1.3.99.1) at 51 +/- 1 degrees C resulted in a higher degree of inhibition in middle-aged and old than in young lizards. The oxaloacetate inhibition of SDH activity and that of oxygen uptake of liver homogenates after 1 h of incubation also showed a similar pattern of age dependency. With increase in time interval (from 15 to 60 min) the young and to some extent the middle-aged lizards showed a partial recovery from inhibition of oxygen consumption of liver homogenates, but not the old animals.
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PMID:Thermal inactivation and oxaloacetate inhibition of hepatic respiratory metabolism in male garden lizards of three different age-groups. 728 49

The initiating factor in ARDS is a matter of controversy. Some investigators relate ARDS development to diffuse pulmonary microemboli after stress ranging from sepsis to non-thoracic and thoracic trauma. Others indicate hyperoxic exposure as the causative agent. This investigation looked for a common factor in ischemia and hyperoxic exposure in lung which could cause the genesis of ARDS. Studies of oxidative phosphorylation, succinate dehydrogenase activity and ATP level were performed on ischemic and 100% O2 exposed lung. Results in both showed decreased respiration rate below the basal rate, decreased SDH activity, followed by marked decrease in ATP levels in pulmonary tissue. Decrease in respiration (ATP production) capacity and ATP levels in ischemic lung were such that normal cell functions could not be sustained if returned to normal circulation. Hyperbaric O2 therapy would subsequently decrease energy metabolism in regions of normal circulation and in previously ischemic regions.
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PMID:A common denominator in the etiology of adult respiratory distress syndrome. 743 54

Succinate oxidation in scutella of germinating seeds of wheat and maize was investigated. Besides oxidation via succinate dehydrogenase (SDH; EC 1.3.99.1), an alternative path of succinate oxidation insensitive to SDH inhibitors--malonate and thenoyltrifluoroacetone (TTFA)--was revealed. Using isopicnic sucrose gradient it was shown that this path is localized in glyoxysomal membranes. Glyoxysomal succinate oxidase (GSO) converts succinate directly into malate with the production of hydrogen peroxide identified using auxiliary enzymes malate dehydrogenase and peroxidase. GSO is most active during the intensive operation of the glyoxylate cycle (3-5 days of germination). Quinacrine, the inhibitor of flavine-containing oxidases, strongly suppressed the activity of GSO. Km for succinate is 18 mM for GSO from maize scutellum. It is concluded that in scutella of cereal seeds the glyoxysomal succinate oxidation non-linked with ATP synthesis operates.
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PMID:Alternative system of succinate oxidation in glyoxysomes of higher plants. 760 25

The iron-sulfur protein (Ip) subunit of succinate dehydrogenase (SDH and complex II) of the respiratory chain is highly conserved in evolution [Gould et al., Proc. Natl. Acad. Sci. USA 86 (1989) 1934-1938]. We have cloned the entire human Ip cDNA, as well as the Ip-encoding gene (SDH-B) from two genomic human libraries. The cDNA contains a coding sequence of 840 nt, flanked by a 5'-UTR of 133 nt and a 3'-UTR of 123 nt. The entire transcript is encoded by eight exons within approx. 40 kb. The seven introns range in size from 0.75 kb to > 11 kb, and they appear to be of the 'late' intron class. Approx. 5 kb of upstream sequence was also cloned, and approx. 2.4 kb of the promoter region were sequenced and analyzed for consensus elements binding potential transcription factors and transcriptional activators.
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PMID:Structural organization of the gene encoding the human iron-sulfur subunit of succinate dehydrogenase. 762 59

The development of a mitochondrial membrane permeability triggered by the Ca(2+)-stimulation of PLA2 (phospholipase A2; EC 3.1.1.4.) and based on swelling, polyunsaturated fatty acids release and calcium influx, induced the activation of SDH (succinate dehydrogenase; EC 1.3.9.9.) without damaging mitochondria structures. The activity of SDH increased within the length of permeabilization treatment before reaching a plateau. The study of Km and Vm showed that the affinity of SDH for succinate and the maximal velocity were increased. Based on these results, the change of SDH activity triggered under these conditions could be explained by a substrate activation of SDH taking account that the succinate content was significantly enhanced.
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PMID:Study of the succinate dehydrogenase activation in permeabilized mitochondria through the Ca(2+)-stimulated phospholipase A2. 783 34

We investigated the determinants of bone formation at individual remodeling sites (BMUs) in cancellous bone from 8 osteologically normal, sex hormone-replete women with endometriosis. All were tetracycline double-labeled (2, 12, 2, and 4 day regime) before iliac bone biopsy. At each BMU the mineral apposition rate (MAR) was determined conventionally from the distance between label midpoints (MAR 1) and also from the distance between the mineralization front and the trailing edge of the second label (MAR 2). MAR 1 and 2 were compared with within-BMU measurements of osteoid width (O.Wi) and the activities of osteoblastic alkaline phosphatase (AP) and succinic dehydrogenase (SDH, an enzyme in the Krebs cycle), both quantitated by microdensitometry. A total of 143 BMUs were evaluated, of which 88 were satisfactory for all measurements and 132 were satisfactory for all but SDH. There was a weak correlation (r = 0.34) between MAR 1 and 2 at individual sites, with a mean difference of 0.49 micron/day (mean MAR 0.82 micron/day). The mean MAR of individual subjects tended to be either increasing or decreasing (F = 16.1, p < 0.01). In linear regressions, MAR 2 was statistically dependent on O.Wi, AP, and SDH (73% of the variance accounted for). In contrast, MAR 1 was weakly correlated with O.Wi and only 30% of its variance was accounted for by AP, SDH, and O.Wi. The variance in the MAR 2 data was inversely increased (p < 0.01) compared with MAR 1 as the number of days of bone formation represented.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Fluctuation of mineral apposition rate at individual bone-remodeling sites in human iliac cancellous bone: independent correlations with osteoid width and osteoblastic alkaline phosphatase activity. 786 18

Single fibres from tibialis anterior, extensor digitorum longus, gastrocnemius and soleus muscles in young (4-week-old) and adult (35-week-old) Wistar male rats were classified into three types on the basis of their enzyme-histochemical features: slow-twitch oxidative (SO), fast-twitch oxidative and glycolytic (FOG) and fast-twitch glycolytic (FG) fibres. Ultrastructural (volume density of mitochondria: Vmt and Z line width) and metabolic (phosphofructokinase: PFK and succinate dehydrogenase: SDH activities) profiles were measured. PFK activity in all types of fibres was higher in adult rats, and the difference between the two age-groups (adult/young) was largest between FG, FOG and SO fibres respectively. SDH activity and Vmt were lower in adult rats in a similar way in all fibres. A significant positive correlation was observed between the Vmt and SDH activity in both age-groups. This positive correlation was very specific in fast-twitch and slow-twitch fibres. Changes in the Vmt did not relate directly to the changes in fibre cross-sectional area. The overall pattern indicates that glycolytic capacity of fast-twitch fibres in flexor muscles (TA and EDL) is higher than in extensor muscles (GC and SOL), and that oxidative capacity of all types of fibre in extensor muscles is higher than in flexor muscles. These profiles were changed by growth, and may be related to the specific differences in pattern of activity of each skeletal muscle, and may reflect differences in the recruitment order of different muscles.
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PMID:Differences in ultrastructural and metabolic profiles within the same type of fibres in various muscles of young and adult rats. 801 Jan 40


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