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)

We investigated the relationship between energy-rich phosphate content and muscle fiber-type composition in human skeletal muscle using a combination of 31P-nuclear magnetic resonance spectroscopy (NMR), histochemical, and biochemical analyses of muscle biopsies. Localized 31P spectra were collected simultaneously from the predominantly slow-twitch soleus muscle and the mixed (fast-twitch and slow-twitch) medial and lateral gastrocnemius muscles, using B1-insensitive Hadamard Spectroscopic Imaging. Biopsy samples were taken from the soleus and lateral gastrocnemius muscles before NMR investigation and analyzed for fiber type composition and succinic dehydrogenase (SDH) activity. Fiber-type composition was determined based both on myofibrillar actomyosin ATPase activity combined with cross-sectional area and on myosin heavy-chain composition. Localized spectroscopy demonstrated a significantly (P < 0.001) higher P(i)/phosphocreatine ratio in the soleus muscle (0.15 +/- 0.01) compared with the medial (0.12 +/- 0.01) and lateral (0.10 +/- 0.0) gastrocnemius. However, in vitro analysis of muscle biopsies showed only a moderate relationship between the basal phosphate content and myofibrillar actomyosin ATPase-based fiber-type composition and SDH activity, respectively.
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PMID:Energy-rich phosphates in slow and fast human skeletal muscle. 773 35

To study the aging of muscle fibres in red skeletal muscle, fibre number, fibre diameter and fibre type composition in the soleus muscle of male rats of 3, 12 and 24 months old were examined. The total number of muscle fibres remained unchanged, while average diameter increased slightly with increasing age. The staining intensity of myosin adenosine triphosphatase (ATPase) activity in the fibres decreased with advancing age. Therefore, observation on the basis of myosin ATPase histochemistry alone is not adequate to study the aging of muscle fibres. In the muscles of 24 month-old animals, four fibre types were recognized; 1) many (52%) type I-O fibres showing weak ATPase and succinate dehydrogenase (SDH) reactions with slight subsarcolemmal aggregates of diformazan (SAD); 2) some (33%) type M fibres showing weak ATPase and intense SDH reactions with marked SAD; 3) a few (12%) type O fibres showing weak ATPase and intense SDH reactions without SAD; and 4) very few (4%) type IIA fibres. Histochemical and morphometric results suggest that type I-O, type M and type O fibres are derived from type I, type I and type IIA fibres, respectively. Furthermore, no transitional fibres from type IIA to type I were observed. Therefore, age-related changes in fibre type composition in the muscle cannot be explained by the simple idea that most type IIA fibres are transformed into type I fibres.
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PMID:Age-related changes in fibre number, fibre size, fibre type composition and adenosine triphosphatase activity in rat soleus muscle. 797 39

The relationship between myonuclear number, cellular size, succinate dehydrogenase activity, and myosin type was examined in single fiber segments (n = 54; 9 +/- 3 mm long) mechanically dissected from soleus and plantaris muscles of adult rats. One end of each fiber segment was stained for DNA before quantitative photometric analysis of succinate dehydrogenase activity; the other end was double immunolabeled with fast and slow myosin heavy chain monoclonal antibodies. Mean +/- S.D. cytoplasmic volume/myonucleus ratio was higher in fast and slow plantaris fibers (112 +/- 69 vs. 34 +/- 21 x 10(3) microns3) than fast and slow soleus fibers (40 +/- 20 vs. 30 +/- 14 x 10(3) microns3), respectively. Slow fibers always had small volumes/myonucleus, regardless of fiber diameter, succinate dehydrogenase activity, or muscle of origin. In contrast, smaller diameter (< 70 microns) fast soleus and plantaris fibers with high succinate dehydrogenase activity appeared to have low volumes/myonucleus while larger diameter (> 70 microns) fast fibers with low succinate dehydrogenase activity always had large volume/myonucleus. Slow soleus fibers had significantly greater numbers of myonuclei/mm than did either fast soleus or fast plantaris fibers (116 +/- 51 vs. 55 +/- 22 and 44 +/- 23), respectively. These data suggest that the myonuclear domain is more limited in slow than fast fibers and in the fibers with a high, compared to a low, oxidative metabolic capability.
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PMID:Cytoplasm-to-myonucleus ratios and succinate dehydrogenase activities in adult rat slow and fast muscle fibers. 811 46

1. The mechanical, morphological and biochemical properties of single motor units from the anterior compartment of the tibialis anterior muscle in adult cats were studied six months after the nerve branches to that compartment were cut and resutured in close proximity to the muscle. 2. In these self-reinnervated muscles, the maximum tetanic tensions were lower in slow than fast units, a relationship similar to that observed among motor units from control adult muscles. The maximum tetanic tensions produced by the fast units were larger than those produced by the same motor unit types in control muscles. Direct counts of muscle fibres belonging to a motor unit showed that factors controlling the number of muscle fibres innervated by a motoneurone type persist during the reinnervation process in that fast motoneurones reinnervated more muscle fibres than slow motoneurones. Thus, the number of muscle fibres reinnervated by a motoneurone principally accounted for the difference in the maximum tension outputs among motor unit types, a relationship similar to that observed in control tibialis anterior muscles. 3. Monoclonal antibodies for specific myosin heavy chains were used to differentiate fibre types. By this criterion, motor units from control muscles were found to contain a homogeneous fibre type composition. In contrast, a heterogeneous, yet markedly biased, fibre type composition was observed in each unit analysed from self-reinnervated muscles. 4. Although not all of the muscle fibres of a motor unit developed the same type-associated parameters after reinnervation, the relationships among myosin heavy chain profile, succinate dehydrogenase activity and the fibre size were similar in fibres of control and self-reinnervated muscles. 5. The processes which dictate both motor unit size and the matching between motoneurone and muscle fibre type during the reinnervation process must be interdependent and result from a hierarchy of decisions which reflects their relative importance. The mechanisms responsible for these two processes may be a combination of: (1) selective innervation which may or may not incorporate a pruning process if multiple synaptic connections are initially formed and/or (2) conversion of enough fibres of a motor unit to form a predominant type.
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PMID:Evidence of incomplete neural control of motor unit properties in cat tibialis anterior after self-reinnervation. 814 36

The objectives of the present study were to determine the size and enzyme properties of soleus fibers of rats subjected to a 4-day spaceflight (National Aeronautics and Space Administration, STS-41) and the effects of exogenous growth hormone (GH) on the atrophic response of the muscle. Four groups of rats were studied: 1) control (Con), 2) Con plus GH treated (Con + GH), 3) flight (Fl), and 4) F1 plus GH treated (Fl + GH). Cross-sectional area and the activities of succinate dehydrogenase and myofibrillar adenosinetriphosphatase (ATPase) were determined in fibers identified in frozen serial cross sections. Fibers were categorized immunohistochemically as slow, fast, or slow-fast on the basis of their reaction with slow and fast myosin heavy-chain (MHC) monoclonal antibodies. Fibers also were categorized as light or dark on the basis of their staining for ATPase at pH 8.6. After the 4-day flight, mean body weight was significantly decreased compared with control. The absolute and relative (muscle wt/body wt) soleus weights were significantly smaller in the Fl and Fl + GH rats compared with their respective ground-based controls. In both flight groups, the cross-sectional area of the light ATPase fibers was significantly smaller (approximately 30%) than control. Three of 11 flight rats had a higher proportion of fibers expressing both slow and fast MHCs than expected on the basis of the fiber type distribution in the 11 control rats. Mean fiber succinate dehydrogenase and ATPase activities were similar among the four groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Absence of a growth hormone effect on rat soleus atrophy during a 4-day spaceflight. 845 66

The distribution of collagen fibers of rat masticatory muscles during the postnatal period (two weeks), was investigated by electrophoresis and immunohistochemistry. At these stages, the myosin of rat masticatory muscles displays specific electrophoretic patterns. Comparison of the myosin patterns of these muscles allows their identification. 1) Analysis by SDS-PAGE indicated that one of three weakly reactive stainable proteins with lower mobility than the heavy chain of myosin disappeared from the temporal muscle on day 13, as compared with other masticatory muscles. However, in histochemical analysis of the muscle fibers, the reaction specific for succinic dehydrogenase (SDH) activity was strong, and the fibers on day 13 could be classified into two types with respect to SDH activity. By contrast, on day 0, the fibers were classified into two types with respect to myosin ATPase activity. 2) Immunohistochemical analysis indicated that the distribution of the components of the extracellular matrix in the epimysium (type I collagen), perimysium (type I collagen, fibronectin, and laminin) and endomysium (type III collagen, fibronectin, laminin, and tenascin) was related to the metabolic capacity on days 12 to 13. The variability in the types of myosin and in proteins of the extracellular matrix might be important during the development of rat masticatory muscles.
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PMID:Distribution of the macromolecular components of masticatory muscles during differentiation of the muscle fibers in the postnatal rat. 857 Jan 40

Motor units in cat diaphragm and tibialis posterior muscles were classified physiologically as slow-twitch, fast-twitch, fatigue-resistant, fast-twitch fatigue-intermediate, or fast-twitch fatigable. Motor unit fibers were then identified by glycogen depletion and classified as type I, IIa, IIb, or IIx on the basis of myofibrillar adenosinetriphosphatase-staining profiles and immunoreactivity for myosin heavy-chain (MHC) isoforms. In both muscles, slow-twitch and fast-twitch fatigue-resistant units comprised type I and IIa fibers expressing MHC-slow and MHC-2A isoforms, respectively. Fast-twitch fatigue-intermediate and fast-twitch fatigable units comprised type IIx fibers expressing the MHC-2X isoform. Some fast-twitch fatigue-intermediate units had a mixed composition with a few fibers (approximately 10%) expressing the MHC-2A isoform. Motor unit fiber succinate dehydrogenase (SDH) activity was quantified, and variability was estimated by the interquartile range, which was lower among motor unit fibers than in adjacent fibers of the same histochemical type but comparable to that along the length of individual fibers. We conclude that, despite the mixed-MHC phenotype of some diaphragm and tibialis posterior motor units, SDH activity is relatively uniform. This supports the hypothesis that motoneurons exert a predominant influence on muscle fiber SDH activity.
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PMID:Myosin phenotype and SDH enzyme variability among motor unit fibers. 880 28

Five goat latissimus dorsi muscles (LDM) were submitted to a progressive chronic electrostimulation program to reach an integrated understanding of the fast-to-slow transformation process in large mammals. LDM were regularly sampled and followed during a period of 8 months. Each sample was simultaneously assessed for histoenzymological study, myosin and LDH isoforms and bioenergetic capacities [NADH dehydrogenase cytochrome c oxidoreductase (NADH Cyt c OR), succinate dehydrogenase cytochrome c oxidoreductase (Succ Cyt c OR), cytochrome c oxidase (Cyt c Ox) and LDH]. Such muscles were also tested with and without completion of II to I transformation for their mechanical properties in isometric and isotonic strain gauge testing. The conversion of fast-to-slow myosin monitored by heavy chain (HC I) and light chain slow component (LC2s) began a few days after stimulation and was almost 100% after 100 days. The H-LDH isoforms evolved similarly but did not reach 100% conversion after 200 days. The activity of respiratory chain oxidases increased within 36 h but to a variable extent and peaked after 32 days, corresponding to a 75% transformation of myosin compared to initial levels. NADH Cyt c OR, Succ Cyt c OR, and Cyt c Ox, respectively increased 10-, 5- and 5-fold. These activities then significantly decreased before the completion of the myofibrillar transformation and reached a plateau with stable activities that remained 2- to 3-fold higher than the unstimulated LDM. LDH activity sharply decreased until day 62 (5-fold) and then plateaued. Functionally, muscle showed a reduced speed of contraction and moderate reduction in power output but had become fatigue-resistant. This study documents the transformation process in large mammals and suggests the dynamic relation between workload, aerobic-anaerobic metabolism and the contractile myofibrillar system.
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PMID:Type II to type I transformation of chronically stimulated goat latissimus dorsi muscle: a histoenzymological, biochemical, bioenergetic, and functional study. 883 65

We studied the coordinated regulation of myosin heavy chains (MHC) and metabolic enzymes within individual overloaded adult rat plantaris fibers. This was done using monoclonal antibodies raised against distinct developmental and adult MHCs, and quantitative microphotometric succinate dehydrogenase (SDH) and glycerol-3-phosphate dehydrogenase (GPDH) enzyme assays. Overload shifted MHC expression in the order IIb-->IIx-->IIa-->alpha/I, with a tripling of cells coexpressing I and alpha-MHC, and a transient reexpression of two embryonic MHC and the neonatal isoform in preexisting myofibers. Overload caused a rapid, size-independent, 50% decrease in GPDH activity across all cell types, which recovered by 6 wk. Fiber SDH activities varied according to MHC composition, such that overloaded fibers coexpressing IIa MHC displayed control slow fiber SDH levels, whereas cells expressing IIx and IIb MHC displayed a transient 30% increase in SDH that recovered by 6 wk. Our results suggest that during overload, fibers adapt progressively to the new functional requirements and display more efficient cellular energy utilization and delivery characteristics. The time course of adaptations suggests a role for glycolytic enzymes in the initiation of these transformations.
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PMID:Coordinated expression of myosin heavy chain isoforms and metabolic enzymes within overloaded rat muscle fibers. 927 35

The superior rectus muscle fibers of marlins, swordfish, sailfish and spearfish are modified for heat production at the expense of contractile ability. Although 'heater cells' are a muscle derivative (Block, 1986, 1991), the myoblast origin and developmental pathway of these thermogenic cells is unknown. To gain insight into heater cell origins, we characterized blue marlin superior rectus muscle and its heater tissue derivative with histochemical and immunological techniques. We specifically employed myosin ATPase and succinate dehydrogenase histochemical assays, and myosin heavy chain immunohistochemistry. Results revealed that marlin superior rectus muscles contain at least six distinct fiber types, and suggested the presence of both twitch and tonic fibers. Immunological results indicate that myosin is present within the thermogenic cells but not in myofibrillar lattices. The antibodies that recognized myosin in heater cells also labeled myosin in the twitch fibers of swimming muscle. In contrast, antibodies that labeled histologically defined tonic fibers did not label heater cells. These results suggest that heater cells and twitch fibers express the same myosin isoform, and establish a phenotypic connection between heater cells and twitch fibers. This conclusion is discussed in the context of the muscle-to-heater trajectory and the muscle fiber-type origin of heater cells.
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PMID:Histochemical and immunohistochemical studies on the origin of the blue marlin heater cell phenotype. 946 27


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