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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 authors studied the histochemical and ultrastructural alterations of human muscles after spontaneous rupture of the tendon. Both
succinate dehydrogenase
(in type 1 fibres), and
ATPase
(in type 2 fibres) activity decreased in all injured muscles. In the intact antagonists and in contralateral muscles alterations were not found. The creatine phosphokinase and aldolase activity were decreased also in the injured muscles. The lactate dehydrogenase activity was various both in affected and in unaffected antagonists muscles. 2 weeks or more after the rupture of the tendon, in the injured muscles the number of type 1 fibres were decreased and therefore a statistically significant type 2 fibre predominance occurred. Ultrastructurally the disruption and disorientation of the myofibrils, streaming and disorganisation of Z line were found. The sarcolemma was arranged, the sarcoplasmic reticulum was dilated; both normal, pycnotic and enlarged mitochondria were observed. The motor end-plates were not discernible.
...
PMID:Histochemical and ultrastructural study of human muscles after spontaneous rupture of the tendon. 15 81
Ligature and section of the abdominal aorta results in only minor and temporary functional and metabolic changes in the slow soleus muscle of the rat. A very small decrease in maximal tetanic tension corresponds to a few scattered areas of damaged and necrotic muscle fibres, in which decreased
succinic dehydrogenase
and loss of phosphorylase activity was observed. A new experimental approach, i.e. ligature and section of the abdominal aorta combined with terminal devascularisation, preserving intact tendons and innervation of the muscle causes maximal muscle ischemia, followed by an almost complete loss of tetanic tension output, marked shortening of contraction time and profound morphological and histochemical changes. The decrease in
succinic dehydrogenase
and
ATPase
activities and loss of phosphorylase activity occur in the majority of degenerating muscle fibres except for a thin rim of peripheral fibres during the first 4 days. Subsequently, the contractile properties recover gradually and enzyme activities reappear in the regenerating muscle fibres simultaneously with new revascularisation. Thirty days after the operation all the parameters observed returned to control values.
...
PMID:Effect of ischemia on contractile and histochemical properties of the rat soleus muscle. 15 45
Differential centrifugation of rat small intestinal homogenates produced a crude brush border (BB) fraction that was enriched 15-fold for the marker enzymes, alkaline phosphatase and sucrase; contamination with mitochondrial enzymes, monoamine oxidase and
succinate dehydrogenase
, was minimal. ATP hydrolysis by this BB fraction was stimulated by addition of several anions to the incubation medium: HCO3 and Cl were equally effective in this regard, with NO3, NO2, SO4, and acetate being less stimulatory. SCN and CNO inhibited
ATPase
activity, whereas the divalent anion SO3 was stimulatory at low concentrations (less than 25 mM) but inhibitory at 100 mM. Maximum anion stimulation was observed at a Mg concentration of 0.5 mM, and pH optimum was 8.5. Kinetic analysis showed that HCO3 increased the Vmax without altering the Km for ATP; the Ka for this effect of HCO3 was 35 mM. This enzyme activity was completely inhibited by 20 mM L-phenylalanine, 10 mM L-cysteine, and 3 mM EDTA, compounds that also inhibited intestinal alkaline phosphatase. These results demonstrate the presence of anion-stimulated
ATPase
activity in rat small intestinal brush border and suggest that this activity may be related to intestinal alkaline phosphatase. The role of this enzyme in intestinal transport is not known, but could relate to the regulation of intestinal absorption and secretion.
...
PMID:Anion-stimulated ATPase activity of brush border from rat small intestine. 15 3
A new technique for isolating fragmented plasma membranes from skeletal muscle has been developed that is based on gentle mechanical disruption of selected homogenate fractions. (Na+ + K+)-stimulated, Mg2+-dependent
ATPase
was used as an enzymatic marker for the plasma membrane, Ca2+-stimulated, Mg2+-dependent
ATPase
as a marker for sarcoplasmic reticulum, and
succinate dehydrogenase
for mitochondria. Cell segments in an amber low-speed (800 x g) pellet of a frog muscle homogenate were disrupted by repeated gentle shearing with a Polytron homogenizer. Sarcoplasmic reticulum was released into the low-speed supernatant, whereas most of the plasma membrane marker remained in a white, fluffy layer of the sediment, which contained sarcolemma and myofibrils. Additional gentle shearing of the white low-speed sediment extracted plasma membranes in a form that required centrifugation at 100,000 x g for pelleting. This pellet, the fragmented plasma membrane fraction, had a relatively high specific activity of (Na+ + K+)-stimulated
ATPase
compared with the other fractions, but it had essentially no Ca2+-stimulated
ATPase
activity and only a small percentage of the
succinate dehydrogenase
activity of the homogenate. Experimental evidence suggests that the fragmented plasma membrane fraction is derived from delicate transverse tubules rather than from the thicker, basement membrane-coated sarcolemmal sheath of muscle cells. Electron microscopy showed small vesicles lined bu a single thin membrane. Hydroxyproline, a characteristic constituent of collagen and basememt membrane, could not be detected in this fraction.
...
PMID:Isolation of plasma membrane vesicles, derived from transverse tubules, by selective homogenization of subcellular fractions of frog skeletal muscle in isotonic media. 15 42
The serratus metapatagialis (SMP) muscle of the pigeon has been studied histochemically and ultrastructurally. At the gross anatomical level the SMP is clearly divisible into a peripheral whitish band and a red portion comprised predominantly of 'pale' and 'red' fibres respectively. The pale fibres possess low
succinate dehydrogenase
, low mitochondrial content, absence of subsarcolemmal mitochondrial aggregates, low fat, moderate glycogen, high phosphorylase, low-to-moderate regular myofibrillar adenosine triphosphatase (M-ATPase), activation of M-
ATPase
following acid preincubation and jagged Z bands. On the basis of these characteristics, these physiologically slow muscle fibres have been termed 'Type I white or slow-twitch glycolytic'. The SMP red fibres, however, possess high aerobic as well as glycolytic capacity, high M-
ATPase
activity which is labile after acid preincubation and thick but straight Z bands; therefore, they are the 'Type II red or fast-twitch oxidative-glycolytic'.
...
PMID:Histochemical and ultrastructural characteristics of a new muscle fibre type in avian striated muscle. 15 9
Trimmed strips of sternomandibularis muscles taken from freshly-slaughtered cattle were placed in an isotonic myograph and cooled to 1 degree C. Spontaneous activity due to neuromuscular irritability was minimized by keeping muscle surfaces moist and anaerobic and was monitored by electromyography. Muscle strips were removed and frozen for histochemical analysis after they had completed their initial phase of cold-induced shortening (several hours). Control strips maintained for an equal time at 24 degrees C rarely depleted the stainable glycogen in any of their muscle fibres so as to become PAS-negative. In chilled muscle strips, however, glycogenolysis was activated in some muscle fibres and they became PAS-negative. In serial sections, most of the PAS-negative fibres exhibited strong
ATPase
and weak
succinate dehydrogenase
activity. Fibres with weak
ATPase
and strong
succinate dehydrogenase
activity rarely became PAS-negative. These results are in agreement with biochemical reports of a cold-induced (less than 5 degrees C) activation of glycolysis in skeletal muscle post mortem. Investigations on untrimmed lengths of excised sternomandibularis muscle indicated that longitudinal muscle damage caused in cutting muscle strips for the myograph and/or their more rapid rate of initial cooling had facilitated the depletion of stainable glycogen.
...
PMID:Low temperature activation of post mortem glycogenolysis in bovine skeletal muscle fibres. 15 72
Folate nephropathy was selected as a model to study renal mitochondrial response after tubular injury. 20 h after injection, 14C-leucine incorporation was suppressed to 20--30% of control, 14C-mannose incorporation was 63--78% greater than control while the activities of
succinic dehydrogenase
and monoamine oxidase were unaltered. By 40 h, 14C-leucine incorporation had been restored to control values. Also, at 20 h,
ATPase
activity sensitive to oligomycin inhibition had increased by 45--73%, whereas K+-stimulated
ATPase
activity was reduced in the experimental mitochondrial fractions. The results are discussed along with other studies of mitochondria in experimental renal disease.
...
PMID:Alterations of mitochondrial properties in folate nephropathy. 16 16
1. Functional properties of the
ATPase
complex are investigated in megamitochondria isolated from livers of weanling mice fed a diet containing 2% chloramphenicol, as an inhibitor of mitochondrial protein synthesis. 2. Whereas the specific activity of
ATPase
remains unchanged in chloramphenicol-induced megamitochondria, about 40% of the enyzme activity is resistant to inhibition by oligomycin, triethyltin or venturicidin. It is concluded that the
ATPase
complex lacks one or more components whose synthesis or accumulation is dependent on mitochondrial translation. The inhibitor-resistant
ATPase
portion appears tightly bound to the mitochondrial membrane. 3. Respiratory chain phosphorylation is tightly coupled in isolated megamitochondria. ATP synthesis and ATP-Pi exchange are diminished by 40%, as compared to control mitochondria, but both processes are sensitive to oligomycin, triethyltin or venturicidin. 4. The decrease in ATP synthesis and ATP-Pi exchange in megamitochondria correlates quite well with the emergence of inhibitor-resistant
ATPase
. 5. The following electron transport activities in the megmitochondria are reduced: NADH-cytochrome c reductase, by 60%, cytochrome oxidase, by 80%; the amount of antimycin required to gain complete inhibition of the bc1-segment is diminished by more than 50%. On the other hand
succinate dehydrogenase
activity is increased by 50%. 6. Chloramphenicol-induced megamitochondria appear to be a useful system for studying the role of mitochondrial translation in the assembly of mammalian mitochondria.
...
PMID:ATPase complex and oxidative phosphorylation in chloramphenicol-induced megamitochondria from mouse liver. 17 30
Plasma membranes were isolated from rat liver mainly under isotonic conditions. As marker enzymes for the plasma membrane, 5'-nucleotidase and (Na+ + K+)-
ATPase
were used. The yield of plasma membrane was 0.6-0.9 mg protein per g wet weight of liver. The recovery of 5'-nucleotidase and (Na+ +K+)-
ATPase
activity was 18 and 48% of the total activity of the whole-liver homogenate, respectively. Judged from the activity of glucose-6-phosphatase and
succinate dehydrogenase
in the plasma membrane, and from the electron microscopic observation of it, the contamination by microsomes and mitochondria was very low. A further homogenization of the plasma membrane yielded two fractions, the light and heavy fractions, in a discontinuous sucrose gradient centrifugation. The light fraction showed higher specific activities of 5'-nucleotidase, alkaline phosphatase, (Na+ +K+)-
ATPase
and Mg2+-ATPase, whereas the heavy one showed a higher specific activity of adenylate cyclase. Ligation of the bile duct for 48 h decreased the specific activities of (Na2+ +K+)-
ATPase
and Mg2+-ATPase in the light fraction, whereas it had no significant influence on the activities of these enzymes in the heavy fraction. The specific activity of alkaline phosphate was elevated in both fractions by the obstruction of the bile flow. Electron microscopy on sections of the plasma membrane subfractions showed that the light fraction consisted of vesicles of various sizes and that the heavy fractions contained membrane sheets and paired membrane strips connected by junctional complexes, as well as vesicles. The origin of these two fractions is discussed and it is suggested that the light fraction was derived from the bile front of the liver cell surface and the heavy one contained the blood front and the lateral surface of it.
...
PMID:Subfractionation of rat liver plasma membrane. Uneven distribution of plasma membrane-bound enzymes on the liver cell surface. 17 48
Temperature-responsive microsomes of the ciliate protozoan Tetrahymena have been originally fractionated by step centrifugation on two-layered, Mg2+-containing sucrose gradients. Three fractions have been obtained, which are termed smooth I, smooth II and rough according to the appearance of the membrane vesicles upon electron-microscopy. Smooth I, smooth II, and rough microsomes exhibit RNA/protein ratios of 0.09, 0.20, and 0.34; their phospholipid/protein ratios and their neutral lipid/phospholipid ratios were 0.52, 0.43 and 0.25, and 0.17, 0.18 and 0.13, respectively. All three fractions contain equivalent, low
succinic dehydrogenase
and 5'-nucleotidase activities. Glucose-6-phosphatase and acid phosphatase are more concentrated in smooth I membranes than in rough membranes. The reverse is true for
ATPase
. The smooth II membranes occupy an intermediate position except that their
ATPase
activity is the lowest of the three fractions. The specific activities of these enzymes of the three microsomal fractions are compared to those of homogenates of whole cells. Thin-layer chromatography reveals a very similar polar and nonpolar lipid pattern of the three microsomal fractions. The major phospholipid compounds are phosphatidlethanolamine, glycerideaminoethylphosphonate and phosphatidylcholine, while diglycerides, an unknown NL-compound, and triglycerides are the major apolar lipids. Gas liquid chromatography shows that the fatty acids are mainly even-numbered ranging between C12 and C18. The smooth I, smooth II and rough membranes contain 65.2, 69.3 and 72.7% unsaturated fatty acids in their polar lipids, whereas only 52.7, 49.7 and 48.3% unsaturated acids are found in their apolar lipids, respectively. The fatty acids are more unevenly distributed among the individual polar lipids than in the apolar ones.
...
PMID:Membranes of Tetrahymena. IV. Isolation and characterization of temperature-responsive smooth and rough microsomal subfractions. 17 62
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