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)

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

Surgical cardiac denervation was carried out in dogs under halothane anaesthesia. In a paired experimental design control biopsy specimens were obtained before surgical denervation. The dogs were allowed to recover and three weeks to elapse before the second biopsy specimen was taken. Both right and left ventricular specimens had higher in vitro oxygen consumption after denervation than before. Other specimens were immediately cooled in hexane at -60 degrees C and stored under liquid nitrogen until analysed. Succinate dehydrogenase and cytochrome oxidase activities were then measured histochemically in sequential 10 or 12 microns sections. There was no significant difference between the enzyme activities measured before or after cardiac denervation (succinate dehydrogenase 20.3(6.3) before, 19.4(4.02) pmol.H2.cm-2.s-1, after; cytochrome oxidase 223(73.4) before, 263(61.6) (measured as extinction coefficient) after). Thus the changes in oxygen consumption in the chronically denervated dog heart are not due to any lack of these mitochondrial enzymes.
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PMID:Effect of lack of noradrenaline on myocardial oxygen consumption in denervated dog hearts. 282 57

The sensory projections from the whiskers of mice and other rodents synapse somatotopically in 3 subnuclei in the brainstem trigeminal complex, in the ventrobasal complex of the thalamus and in the somatosensory cortex. Deafferentation of the whiskers in adult animals results in qualitative and quantitative changes in activities of the metabolic enzymes in the somatosensory cortex (e.g. J. Neuro-sci., 1 (1981) 929-935). We determined the time course and extent of changes in the subcortical trigeminal centers of adult mice after deafferentation. The right infraorbital nerve was sectioned in mice under surgical anesthesia; the animals survived for periods up to 26 weeks. The optic nerve was also cut to evaluate the effects of central tract section. Some brains were prepared histochemically for the mitochondrial enzymes cytochrome oxidase (CO) and succinic dehydrogenase (SDH), and some were prepared for microchemical analysis of the enzymes citrate synthase (CS), malate dehydrogenase (MDH) and phosphorylase. All deafferented and intact nuclei were examined in each animal quantitatively. The oxidative enzymes (CO, SDH, CS and MDH) that were analyzed by histochemical and microchemical approaches showed a decrease in activities as early as 3 weeks postdeafferentation, a trend that continued up to 12 weeks in all the subcortical trigeminal stations and lateral geniculate nucleus (LGN) when compared with the intact side. By 25 weeks postlesion, the levels were comparable to the intact side except that in the LGN, the levels remained depressed. The phosphorylase levels increased at around 3 weeks postoperation and remained elevated 25 weeks postlesion. Each case provided results on the effects of deafferentation at a given time point throughout the trigeminal pathway. Direct quantitative correlation of histochemical and microchemical approaches for glycolytic enzymes is consistent with a coordinate regulation of these molecules. The changes in enzyme levels in all nuclei occur simultaneously and to a similar degree. This strongly suggests that neuronal activity plays an important role in regulating metabolic machinery throughout this pathway in adults.
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PMID:Quantitative histochemical and microchemical changes in the adult mouse central nervous system after section of the infraorbital and optic nerves. 303 55

It is demonstrated by experiments with rabbits that the Ca2+-ATP-ase activity is stabilized when using combined anesthetics (diacetylcholine + halothane + N2O) as distinct from application of halothane. A decrease in the cholinesterase activity is less pronounced than under the halothane action but more than with the diacetylcholine application. A decrease in the Na+, K+-ATP-ase activity is observed with all types of anesthesia. A considerable inhibition of creatine kinase under the action of combined anesthesia and halothane and an increase of the lactate dehydrogenase activity under diacetylcholine application in mitochondria are shown. Reliable differences in the succinic dehydrogenase activity are not detected.
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PMID:[Effect of combined anesthetics on the activity of various myocardium enzymes]. 303 46

1. Long-term electrical stimulation was given to the peroneal nerve of deafferented hindlimbs in hemispinalized adult cats. The amount of stimulation covered 0.5-5.5% of total time per day, different in different animals. For some aspects of the present study, use was also made of cats subjected to "tonic" patterns of chronic stimulation (typically covering 50% of total time; 10, 16). 2. In a terminal acute experiment under general anesthesia, performed after 4 or 8 wk of long-term stimulation, one of the treated peroneal muscles (m. peroneus longus, PerL) was used for measurements of the resistance to contractile fatigue. The fatigue test consisted of 0.33-s bursts of motor-nerve stimulation at 40 Hz, repeated once a second for 4 min (6, 7). During this fatigue test, the evoked compound spikes of the muscle were recorded by electromyographic (EMG) techniques. Following the physiological procedures, PerL was removed for further histochemical analysis. In transverse sections, measurements of optical density were made in central regions of single fibers after staining for the activity of an oxidative enzyme, succinate dehydrogenase (core SDH). 3. Findings from chronically stimulated PerL muscles were compared with three kinds of control PerL muscles: 1) those contralateral to the stimulated ones, 2) those from the operated side of animals that had been deafferented and hemispinalized but not subjected to chronic stimulation, and 3) those from untreated normal animals. 4. Stimulation patterns covering both greater than or equal to 50% and 5-5.5% of daily time gave a marked improvement of fatigue resistance. Pulse rate seemed of little importance for these effects. The pattern covering only 0.5% of total daily time caused no increase of contractile endurance beyond that of normal muscles. 5. During the fatigue test of a control muscle (see above), the amplitude of the compound EMG spikes typically showed a marked decline. This "EMG depression" was effectively counteracted by all the present patterns of chronic stimulation, including the 0.5% pattern. 6. Fibers of chronically stimulated muscles became more similar to each other with respect to their density of core SDH staining. However, among muscles treated during 0.5-5.5% of total daily time, the degree and pattern of change in core SDH staining was not related to the amount and pattern of chronic stimulation or to the resulting degree of contractile endurance.
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PMID:Effects of physiological amounts of high- and low-rate chronic stimulation on fast-twitch muscle of the cat hindlimb. II. Endurance-related properties. 365 85

Chloroform anesthesia induced some histochemical changes in hepatic lobules in the form of diminution in succinic dehydrogenase and acid phosphatase activities accompanied by an increase in alpha esterase activity. In this respect more manifest changes were observed as a result of the delayed effect of chloroform as well as after administration of the inducer.
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PMID:Hepatic histochemistry after chloroform effects of pretreatment with an enzyme inducer. 407 34

A previous study of endotoxemia in dogs demonstrated that exogenous prostacyclin (PGI2), normally a product of vascular endothelium, restored the cardiac index to normal and improved survival. To account for these results, a study was undertaken to test whether PGI2 would alter isolated rat or dog cardiac mitochondrial function following incubation with plasma from endotoxemic animals. A group of five animals served as anesthetized controls. A second group of seven mongrel dogs was given 1.75 mg Escherichia coli endotoxin/kg and was observed for 5 hours without treatment. Anesthesia did not alter cardiopulmonary function; however, 30 minutes after endotoxin administration, the cardiac index decreased from 148 +/- 25 (mean +/- SD) to 111 +/- 12 ml/kg . min (P less than 0.05) and further decreased to 89 +/- 20 ml/kg . min after 4 hours. Dog plasma obtained 2 to 5 hours after endotoxin infusion, incubated with rat or dog myocardial mitochondria, decreased succinate dehydrogenase (SDH) activity (P less than 0.05) and depressed mitochondrial respiration in the presence of the substrate succinate and adenosine diphosphate (ADP) from 180 to 87 Natoms oxygen/mg protein . min (P less than 0.05). There was no change in oxygen consumption when substrate alone was present, nor did plasma alter the amount of ADP phosphorylation as a function of oxygen consumption. A third group of seven animals, 30 minutes after administration of 1.75 mg endotoxin/kg, was treated with 100 ng/kg . min PGI2 for 3 hours. PGI2 infusion in this group prevented the decrease in cardiac index. Plasma obtained during and after PGI2 infusion did not decrease mitochondrial SDH activity, which remained higher than that in controls (P less than 0.001); mitochondrial respiration was also not altered. A correlation was observed between cardiac index and SDH activity (r = 0.58, P less than 0.001) and between cardiac index and mitochondrial respiration (r = 0.61, P less than 0.001). In PGI2-treated dogs cardiac mitochondria were functionally and structurally normal in contrast to the depression and disruption produced by endotoxemia, as observed by enzymatic assay as well as electron microscopy. These results suggest that endotoxemia depresses cardiac mitochondrial respiration, an event related to the decrease in cardiac index. In contrast, cardiac function and mitochondrial respiration are maintained with PGI2 treatment.
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PMID:Myocardial protection with prostacyclin after lethal endotoxemia. 704 19

Second-order auditory neurons in nucleus magnocellularis (NM) of the chick brainstem undergo a series of rapid metabolic changes following unilateral cochlea removal, culminating in the death of 25% of NM neurons. Within hours of cochlea removal, ipsilateral NM neurons show marked increases in histochemical staining for the mitochondrial enzymes succinate dehydrogenase and cytochrome oxidase. We investigated corresponding ultrastructural changes in NM neurons by preparing animals undergoing unilateral cochlea removal for transmission electron microscopy. We quantified changes in NM mitochondrial volume by stereological methods and qualitatively compared mitochondrial morphology between NM neurons destined to survive and those destined to die after cochlea removal. Within hours of cochlea removal, ipsilateral NM neurons show striking increases in mitochondrial volume (84% at 6 hours and 236% at 12 hours after cochlea removal compared to unoperated, control animals). At 2 week survival times, ipsilateral NM neurons contain fewer mitochondria than contralateral neurons. Surprisingly, anesthesia alone causes short-term increases in NM mitochondrial volume. Animals anesthetized with pentobarbital and ketamine and sacrificed 6 or 12 hours later showed a 45% increase in mitochondrial volume compared to previously unanesthetized animals. NM neurons destined to die within days of cochlea removal can be identified within several hours after deafferentation by the appearance of their ribosomes. We observed qualitative differences in mitochondrial morphology in dying neurons. Mitochondria in neurons destined to die consistently showed mitochondrial swelling and vacuolization indicative of metabolic dysfunction. Similar mitochondrial changes have been reported when mitochondria take up excess calcium. Ultrastructural changes in NM after cochlea removal display features of both programmed and pathological cell death, in which increased intracellular calcium is thought to play a role.
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PMID:Rapid increase in mitochondrial volume in nucleus magnocellularis neurons following cochlea removal. 810 59

The objective of this study was to analyse the effects of isoflurane anesthesia (lasting for 15 or 60 min) and isoflurane anesthesia termination (after 1 or 24 h) on met-enkephalin (MENK) and leu-enkephalin (LENK) levels in discrete brain areas and spinal cord segments in rabbits. Moreover histochemical analysis of activities of succinate dehydrogenase, magnesium-dependent adenosine triphosphatase (Mg++ATP-ase) and acid phosphatase in the striatum and hypothalamus were carried out to evaluate the effects of isoflurane anesthesia on energetic, transport and catabolic processes. Throughout anesthesia (15 and 60 min) and after its termination (1 h) the LENK contents were increased in hypothalamus, hippocampus, mesencephalon and lumbar segment of spinal cord. Moreover, during isoflurane anesthesia and after its termination (1 h) MENK and LENK levels decreased in cervical segment and MENK content dropped in thoracic segment of spinal cord. Histochemical data indicated, that isoflurane enhanced energetic processes as well as exchange processes in neurocytes, glial cells, capillary walls and ependymal cells of the third ventricle. Measurements of acid phosphatase activity provided evidence of no signs of toxicity of isoflurane in the examined areas. The changes in enkephalin levels observed during the isoflurane anesthesia and after its termination depended on the type of examined neuropeptides, as well as on parts of the brain and spinal cord studied. The changes observed after isoflurane administration in enkephalinergic system are discussed with regard to our earlier experiments with halothane and enflurane.
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PMID:Influence of isoflurane on enkephalin levels and on some indicatory enzymes in the central nervous system of rabbits. 943 56

The vomeronasal system in adult humans has commonly been regarded as absent or vestigial, but recently it was found to be more common than previously reported. In this study, a search for the frequency of occurrence of the vomeronasal organ (VNO) was performed by examining the nasal septae of 200 adult patients. The frequency of occurrence was found to vary according to the method of examination. By anterior rhinoscopy, large pits and even deep grooves lined by glistening mucosa were visible in 16% of the people examined. Using nasal endoscopes this ratio increased to 76%. After receiving informed, written consent, from 13 patients undergoing endonasal surgery under general anaesthesia, one VNO was dissected out. Specimens were examined histologically and histochemically for succinic dehydrogenase and alkaline phosphatase enzymes. One specimen was processed for transmission electron microscopy. Two morphologically distinct cell types were differentiated. One cell type was previously suggested to have some of the features associated with nerve cells and could have a sensory function. A possible function for the VNO is postulated.
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PMID:The vomeronasal (Jacobson's) organ in adult humans: frequency of occurrence and enzymatic study. 965 18


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