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

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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)

Influence of protein deficiency on the neurobehavioral toxicity of styrene during gestation and early infancy was studied in rats. Eye opening and fur growth were delayed in rat pups born to dams receiving a low protein diet. These pups also showed a delay in the development of surface and air righting reflexes and cliff avoidance response and a marginal increase in the levels of dopamine and serotonin receptors in comparison to those born to dams receiving a normal protein diet. Alterations in these parameters were more marked in pups born to dams exposed to styrene and receiving a low protein diet. In addition, these pups also showed a significant decrease in the activity of monoamine oxidase, Na+, K(+)-ATPase and succinic dehydrogenase as well as significant increases in motor activity and receptor sensitivity when compared to rat pups born to dams receiving a low protein diet. No significant alterations in behavioral and biochemical parameters were observed in the pups born to dams exposed to styrene and receiving a normal protein diet at this dose level. These results suggest that protein deficiency during early life renders the animals more susceptible to styrene.
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PMID:Increased neurobehavioral toxicity of styrene in protein-malnourished rats. 164 82

Enzyme-histochemical studies were conducted on livers of mice chronically fed griseofulvin (GF) in order to produce Mallory bodies (MBs) in hepatocytes. The development of MBs is associated with derangement of the immunohistochemically detectable intermediate filament (IF) cytoskeleton of the cytokeratin (CK) type, although no strict correlation between appearance or involution of MBs and the cytoskeletal alterations exists. Since the function of the IF cytoskeleton and the relationship of its disturbance to cell injury is unknown, the aim of the present study was to correlate the activities of several key enzymes of cellular metabolic pathways with the disturbance of the cytoskeleton architecture. For that purpose enzyme-histochemistry in combination with immunohistochemical CK-IF stainings were performed on identical sections. In GF-intoxicated mouse livers the normal topography of enzyme activities was disturbed, but no strict colocalization of enzymatic and cytoskeletal changes was found. Glucose-6-phosphatase, a microsomal enzyme involved in glucose output and gluconeogenesis, showed elevated activity in MB-free hepatocytes with diminished immunostainable CK-IF cytoskeleton refuting the concept of a disability of those cells to export glucose. It could indeed indicate that those cells without MBs are in the state of recovery. However, these cells could also resemble "hyperactive foci". Glycogen was decreased in MB-containing hepatocytes with disturbed cytoskeleton, and this feature favours the assumption of cell degeneration. On the other hand, the mitochondrial marker enzymes, i.e. succinate dehydrogenase, cytochrome-c-oxidase and 3-hydroxybutyrate dehydrogenase, remained unchanged in altered hepatocytes. Alkaline phosphatase activity at the canalicular pole of GF-intoxicated hepatocytes was elevated, indicating cholestatic features associated with this disorder. However, since altered hepatocytes did not show impairment of oxido-reductase activities, a severe impairment of bile secretion as a consequence of cell damage is unlikely. Unchanged or even increased ATPase activity of altered hepatocytes also indicated their sustained metabolic abilities. The results presented provide indirect evidence that hepatocytes with disturbed IF cytoskeleton do not significantly differ from normal cells with respect to oxidative metabolism, fatty acid synthesis and gluconeogenesis. This suggests that alterations of the IF cytoskeleton associated with GF intoxication and MB formation have no significant adverse influence on the metabolic functions of liver cells, as far as can be assessed by evaluation by enzyme-histochemical staining of several key enzymes.
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PMID:Enzyme-histochemical studies of griseofulvin-intoxicated mouse livers. 165 25

Brown adipose tissue (Na(+)-K+)-ATPase activity, in vitro glucose uptake and 2-aminoisobutyric acid uptake, as well as mitochondrial GDP-binding and succinate dehydrogenase activity were determined in order to study the relationship between these parameters in control, cold acclimated and cafeteria-fed rats. GDP-binding, (Na(+)-K+)-ATPase and glucose uptake were increased in interscapular brown adipose tissue from cold-acclimated and cafeteria-fed rats, whereas 2-aminoisobutyric acid uptake was only increased in cafeteria-fed rats. GDP-binding and (Na(+)-K+)-ATPase activity showed a high correlation coefficient suggesting a parallel modulation of both systems, which would probably share a common regulation mechanism.
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PMID:Parallel modulation of brown adipose tissue GDP-binding, substrate uptake and (Na(+)-K+)-ATPase activity in the rat. 166 Dec 74

1. Physiological, enzyme-histochemical, biochemical and morphometrical properties of fast-twitch single motor units were compared between young (3-6 months) and old rats (20-24 months) using the glycogen depletion technique. Monoclonal antibodies (mAbs) were used to identify the myosin heavy chain (MHC) composition in the muscle fibres of the motor unit (motor unit fibres) in order to facilitate correlative physiological, histochemical, biochemical and morphometrical studies. 2. Earlier observations on effects of age on contractile properties of fast-twitch motor units were confirmed and extended. That is, the duration of the isometric twitch, and the twitch and tetanus forces, were increased. Further, motor unit fibres were rearranged, occupying a larger territory and displaying an increased innervation ratio in old age, indicating a denervation-reinnervation process. 3. Motor units with muscle fibres expressing the novel IIX myosin heavy chain (MHC) were observed in both young and old animals, and they constituted the predominant motor unity type identified in the old animals. In contrast to the type IIX MHC motor units in the young animals, the type IIX MHC units in old age often contained muscle fibres which expressed either the type IIA or type IIB MHC, although type IIX MHC fibres were in the majority (so called 'IIX' MHC motor units), but motor units containing all these three fibre types were never observed. There were also single fibres co-expressing IIX and IIB MHCs in old age. 4. In the young animals the IIX MHC motor units had a higher (P less than 0.001) resistance to fatigue (fatigue ratio 0.45 +/- 0.11) than the type IIB MHC units (0.03 +/- 0.05), a succinate dehydrogenase (SDH) activity (0.62 +/- .007) intermediate (P less than 0.001) between those of type IIA muscle fibres classified according to myofibrillar ATPase activity after acid pre-incubation, i.e. type IIA ATPase, (0.84 +/- 0.13) and type IIB MHC motor unit fibres (0.20 +/- 0.04), and cross-sectional fibre areas (1650 +/- 320 microns 2) which were similar to those of type IIA ATPase muscle fibres (1460 +/- 150 microns 2) but smaller (P less than 0.001) than type IIB MHC motor unit fibres (4650 +/- 1180 microns 2).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of age on physiological, immunohistochemical and biochemical properties of fast-twitch single motor units in the rat. 166 38

We report a functional and molecular analysis of nine oncocytic tumors of the human thyroid. In all the abundance of mitochondria observed ultrastructurally was accompanied by an increase in enzymatic activities of respiratory complexes 1 (NADH dehydrogenase), 11 (succinate dehydrogenase) IV (cytochrome c oxidase), and V (ATPase). Western blot analysis failed to detect uncoupling protein in the tumors. The elevated respiratory enzyme activities were paralleled by an increase in the mitochondrial DNA content. Restriction analysis of mitochondrial DNA gave no indication of heteroplasmy or other gross alterations. We conclude that the mitochondrial proliferation in oncocytic tumors is probably not the result of a compensatory mechanism for the deficiency in enzyme complexes of the mitochondrial respiratory chain.
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PMID:Functional and molecular analysis of mitochondria in thyroid oncocytoma. 167 11

Inactivation of Na+/K(+)-ATPase activity by the MgPO4 complex analogue Co(NH3)4PO4 leads, in everted red blood cell vesicles, to the parallel inactivation of 22Na+/K+ flux and 86Rb/Rb+ exchange, but leaves the 22Na+/Na(+)-exchange activity and the uncoupled ATP-supported 22Na+ transport unaffected. Furthermore, inactivation of purified Na+/K(+)-ATPase by Co(NH3)4PO4 leads to a parallel decrease of the capacity of the [3H]ouabain receptor site, when binding was studied by the Mg2+/Pi-supported pathway (ouabain-enzyme complex II) but the capacity of the ouabain receptor site was unaltered, when the Na+/Mg2+/ATP-supported pathway (ouabain-enzyme complex I) was used. No change in the dissociation constants of either ouabain receptor complex was observed following inactivation of Na+/K(+)-ATPase. When eosin was used as a marker for the high-affinity ATP-binding site of the E1 conformation, formation of stable E'2.Co(NH3)4PO4 complex led to a shift in the high-affinity ATP-binding site towards the sodium form. This led to an increase in the dissociation constant of the enzyme complex with K+, from 1.4 mM with the unmodified enzyme to 280 mM with the Co(NH3)4PO4-inactivated enzyme. It was concluded, that the effects of Co(NH3)4PO4 on the partial activities of the sodium pump are difficult to reconcile with an alpha, beta-protomeric enzyme working according the Albers-Post scheme. The data are consistent with an alpha 2, beta 2 diprotomeric enzyme of interacting catalytic subunits working with a modified version of the Albers-Post model.
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PMID:Blocking of Na+/K+ transport by the MgPO4 complex analogue Co(NH3)4PO4 leaves the Na+/Na(+)-exchange reaction of the sodium pump unaltered and shifts its high-affinity ATP-binding site to a Na(+)-like form. 169 57

Do muscle fiber properties commonly associated with fiber types in adult animals and the population distribution of these properties require normal activation patterns to develop? To address this issue, the activity of an oxidative [succinic dehydrogenase (SDH)] and a glycolytic [alpha-glycerophosphate dehydrogenase (GPD)] marker enzyme, the characteristics of myosin adenosinetriphosphatase (myosin ATPase, alkaline preincubation), and the cross-sectional area of single fibers were studied. The soleus and medial gastrocnemius of normal adult cats were compared with cats that 6 mo earlier had been spinally transected at T12-T13 at 2 wk of age. In control cats, SDH activity was higher in dark than light ATPase fibers in the soleus and higher in light than dark ATPase fibers in the medial gastrocnemius. After transection, SDH activity was similar to control in both muscles. GPD activity appeared to be elevated in some fibers in each fiber type in both muscles after transection. The cross-sectional areas most affected by spinal transection were light ATPase fibers of the soleus and dark ATPase fibers of the medial gastrocnemius, the predominant fiber type in each muscle. These data demonstrate that although the muscle fibers of cats spinalized at 2 wk of age presumably were never exposed to normal levels of activation, the activity of an oxidative marker enzyme was maintained or elevated 6 mo after spinal transection. Furthermore, although the absolute enzyme activities in some fibers were elevated by transection, three functional protein systems commonly associated with fiber types, i.e., hydrolysis of ATP by myosin ATPase and glycolytic (GPD) and oxidative (SHD) metabolism, developed in a coordinated manner typical of normal adult muscles.
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PMID:Enzyme profiles of single muscle fibers never exposed to normal neuromuscular activity. 170 Sep 75

Synaptosomes isolated from calf brain cortex were lysed and fragmented by Yeda press treatment. The obtained membranes have previously been fractionated in a counter-current distribution process using a liquid-liquid two-phase system consisting of water, dextran, Ficoll and poly(ethylene glycol) [J. Chromatogr., 358 (1986) 147]. Using the fact that there are discrete membrane populations, a rapid preparative method for isolation of the two main fractions is presented in the present work, as well as a subfractionation of one of them using liquid-liquid extraction with dextran-bound Procion yellow HE-3G. The content of several membrane constituents, i.e. protein, acetylcholinesterase, succinate dehydrogenase and ATPase, as well as opiate binding, were determined for the three fractions. Counter-current distribution of the fractions elucidates their heterogeneity and the effectiveness of the purification.
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PMID:Subfractions of membranes from calf brain synaptosomes obtained and studied by liquid-liquid partitioning. 171 38

A study was made of the role of prolactin (PRL) in the regulation of thyroid function in intact animals and in those exposed to stress (swimming was used as physical exercise). A single daily dose of 125 micrograms of PRL per 100 g of body mass was injected subcutaneously in 0.5 ml of saline solution during a week to male rats (control: intact rats; injection of 0.5 ml of saline solution subcutaneously). Redox enzymes; succinate dehydrogenase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, NAD.H2 and NADP.H2, ATPase and monoamine oxidase, total protein, RNA and glycogen in glandular cells were investigated histochemically 24 h after the last injection of PRL or saline, 30 min., 1, 2, 3, 5 and 7 hours after swimming or right after complete fatigue (in the presence of experimental hyperprolactinemia). A conclusion has been made that one of the most important mechanisms of the adaptive effect of PRL is its ability to suppress thyroid function, thus decreasing the metabolism level, which results in reduction of oxygen consumption and improves body tolerance to stress.
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PMID:[Metabolism of thyroid gland cells as affected by prolactin and emotional-physical stress]. 178 Feb 95

Sheep under general anesthesia had their left and right latissimus dorsi muscles mobilized for paraneuroelectrode and pulse generator implantation. After a 10-day recovery period, the left-side muscles were stimulated with a gradually increasing duration and rate over 3 months. At 4 months after operation, the tendinous end of each latissimus dorsi muscle was freed from its humeral insertion and attached to a strain gauge force transducer. Both left and right latissimus dorsi muscles, from each animal, were stimulated to contract for 2 hours for the fatigue study before being isolated, trimmed, and weighed. Frozen tissue biopsies were used to determine creatine phosphate, adenosine triphosphate, lactate, and glycogen content and muscle myosine ATPase, and succinate dehydrogenase activities. The arterial diameter in the conditioned muscle was 30% larger than that of the control muscle and had a 40% higher blood flow at rest. A three- to fivefold increase in blood flow during the fatigue test was observed. The force decreased 47% for the conditioned muscle and 91% for the control muscle. The mass and cross-sectional area of conditioned and unconditioned muscles were similar. Electric conditioning increased fatigue resistant fiber content from 33% to 92%, as evidenced by myosine ATPase activity. During the early phase of the fatigue test, higher glucose uptake but significantly lower lactate production were found for the conditioned muscle. This study indicates that it is possible to produce fatigue resistant muscle with preserved force and mass. In addition to skeletal muscle fiber transformation, metabolic adaptations appear to be important factors for fatigue resistance of skeletal muscle.
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PMID:Fatigue resistant muscle with preserved force and mass for cardiac assist. 180 6


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