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)

Transverse cryostat sections of skeletal muscle were fixed in a solution containing 1.5% glutaraldehyde and 1.5% sulfosalicylic acid and stained in a solution containing equal volumes of 3% hydrogen peroxide and 50% ethanol saturated with o-tolidine. Myoglobin in the sarcoplasm of muscle fibers was precipitated and stained blue. Applicability of this method to cryostat sections, without glutaraldehyde fixations prior to freezing, allowed the myoglobin content of individual muscle fibers to be correlated with other histochemical characteristics of the same fibers seen in serial sections. In the dark red bovine sternomandibularis muscle, fibers with weak adenosine triphosphatase (ATPase) and strong succinate dehydrogenase (SDH) activity always exhibited strong myoglobin staining. An equal degree of staining was found in many fibers with strong ATPase and intermediate to strong SDH activity. Fibers with strong ATPase and weak SDH activity were less strongly stained than the preceding types.
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PMID:A method for myoglobin in cryostat sections of muscle by precipitation with sulfosalicylic acid. 9 25

Myoglobin plays various roles in oxygen supply to muscle mitochondria. It is difficult, and in some cases impossible, to study the relationship between the myoglobin concentration and the oxidative capacity of individual muscle cells because myoglobin has to be fixed in situ whereas determination of oxidative capacity, for example, succinate dehydrogenase activity, requires unfixed cryostat sections. We have investigated whether a vapour-fixation technique allows the use of serial sections to study the relationship between myoglobin and succinate dehydrogenase activity. The technique is used to study a rat soleus muscle, two human skeletal muscle biopsies and biopsies of two patients with chronic heart failure, and in a control and hypertrophied rat heart. Staining intensities were quantified by microdensitometry. The absorbance values were calibrated using sections cut from gelatine blocks containing known amounts of myoglobin. The results show that it is possible to use serial sections for the determination of the myoglobin concentration and succinate dehydrogenase activity, and indicate that myoglobin can lead to a substantial reduction (18-60%) of the extracellular oxygen tension required to prevent an anoxic core in muscle cells.
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PMID:Determination of myoglobin concentration and oxidative capacity in cryostat sections of human and rat skeletal muscle fibres and rat cardiomyocytes. 1504 78

The purpose of this study was to determine the myoglobin concentration in skeletal muscle fibers of chronic heart failure (CHF) patients and to calculate the effect of myoglobin on oxygen buffering and facilitated diffusion. Myoglobin concentration, succinate dehydrogenase (SDH) activity, and cross-sectional area of individual muscle fibers from the vastus lateralis of five control and nine CHF patients were determined using calibrated histochemistry. CHF patients compared with control subjects were similar with respect to myoglobin concentration: type I fibers 0.69 +/- 0.11 mM (mean +/- SD), type II fibers 0.52 +/- 0.07 mM in CHF vs. type I fibers 0.70 +/- 0.09 mM, type II fibers 0.49 +/- 0.07 mM in control, whereas SDH activity was significantly lower in CHF in both fiber types (P < 0.01). The myoglobin concentration in type I fibers was higher than in type II fibers (P < 0.01). Consequently, the oxygen buffering capacity, calculated from myoglobin concentration/SDH activity was increased in CHF: type I fibers 11.4 +/- 2.1 s, type II fibers 13.6 +/- 3.9 s in CHF vs. type I fibers 7.8 +/- 0.9 s, type II fibers 7.5 +/- 1.0 s in control, all P < 0.01). The calculated extracellular oxygen tension required to prevent core anoxia (Po2(crit)) in muscle fibers was similar when controls were compared with patients in type I fibers 10.3 +/- 0.9 Torr in CHF and 11.5 +/- 3.3 Torr in control, but was lower in type II fibers of patients 6.1 +/- 2.8 Torr in CHF and 14.7 +/- 6.2 Torr in control, P < 0.01. The lower Po2(crit) of type II fibers may facilitate oxygen extraction from capillaries. Reduced exercise tolerance in CHF is not due to myoglobin deficiency.
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PMID:Myoglobin concentration in skeletal muscle fibers of chronic heart failure patients. 1966 55