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)

The specific activities (S.A.) of the succinate dehydrogenase-coenzyme Q10 (CoQ10) reductase of a control group of 65 Japanese adults and 59 patients having essential hypertension were determined. The mean S.A. of the hypertensive group was significantly lower (p less than 0.001) and the mean % deficiency of enzyme activity was significantly higher (p less than 0.001) than the values for the control group. These data on Japanese in Osaka agree with data on Americans in Dallas. Some patients showed no CoQ10-deficiency, and others showed definite deficiencies. Emphasizing the CoQ10-enzyme for patient selection, CoQ10 was administered to hypertensive patients. Four individuals showed significant but partial reductions of blood pressure. Monitoring the CoQ10-enzyme before, during, and after administration of CoQ10 indicated responses. The maintenance of high blood pressure could be primarily due to contraction of the arterial wall. Contraction or relaxation of an arterial wall is dependent upon bioenergetics, which also provide the energy for biosynthesis of angiotensin II, renin, aldosterone, and the energy for sodium and potassium transport. A clinical benefit from administration of CoQ10 to patients with essential hypertension could be based upon correcting a deficiency in bioenergetics, and point to possible combination treatments with a form of CoQ and anti-hypertensive drugs.
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PMID:Bioenergetics in clinical medicine. Studies on coenzyme Q10 and essential hypertension. 115 73

Subcellular localization of renin in the rabbit kidney cortex was investigated using two centrifugation techniques. Renin was indirectly assayed on the basis of pressor activity and the reference enzymes such as succinic dehydrogenase, acid phosphatase and D-glucose-6-phosphatase for the other subcellular particulates were biochemically determined. Renin activity was found mainly in the mitochondrial fraction with very little in the microsomal fraction by a differential centrifugation. By a discontinuous sucrose density gradient centrifugation, renin granules were mainly recovered in the fraction corresponding to 1.5 M sucrose, while most of mitochondria, lysosomes and microsome equilibrated in the upper fractions. This renin granular fraction contained approximately 50% of total granular renin activity having a specific activity about six times that seen in the homogenate. After recentrifugation of the renin granular fraction, most of renin activity was recovered in the sediment. Repeated freezing and thawing of this fraction resulted in an increase of renin activity. On the basis of these experimental data it is assumed that renin located in the different subcellular particulates from mitochondria, lysosomes and microsomes in the rabbit kidney cortex.
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PMID:Distribution of renin in subcellular fractions from the rabbit kidney. 118 2

The subcellular localization of renin and kallikrein in rat kidney cortex homogenate was investigated using both differential and density gradient centrifugation techniques. Highest specific activity of renin was found in the heavy mitochondrial fraction. Mitochondrial localization of renin was further supported by the behaviour of succinic dehydrogenase. By differential centrifugation, highest specific activity of kallikrein was found in the light mitochondrial fraction, while by density gradient centrifugation kallikrein was almost completely recovered in the lysosomal fraction. Lysosomal localization of kallikrein is further supported by the behaviour of acid phosphatase. The different subcellular localizations of renin and kallikrein are confirmed and the suggestion that kallikrein is located in the lysosomes is advanced.
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PMID:Subcellular localization of renin and kallikrein in rat kidney. 121 75

The mouse granular convoluted tubules of submandibular gland of laboratory mouse are releasing a range of biologically active peptides (renin, neural growth factor and others) into both the saliva and blood circulation, the males producing it in a larger extent than females. Recently, several from respective peptides were identified to be endogenous ones and brain-related. The present work was aimed to utilise submandibular gland/SMG auto- and isotransplants regenerating in murine brain as a possibly local source of peptides. Experimentally, the newborn and juvenile matured white A breeded mice of both sexes were used. Glandular grafts were grafted into brain parenchyma or CSF spaces. Laboratory animals have then been perished during the first 6 weeks after transplantation, and the transplants so acquired evaluated as serial frontal sections embedded in paraffin and H.E. stained by light microscopy. Also cryocate sections were incubated in order to detect the presence of alkaline phosphatase (AP) and succinic dehydrogenase/(SDH). It was stated experimentally that both mentioned SMG grafts underwent the survival and development intracerebrally. Some first regressive changes were gradually replaced by glandular proliferation and lobular neomorphogenesis having been more pronounced in osotransplants. The proliferative period was characterized by cellular mitoses, multiplication of duct-like and terminal tubulous structures of newly formed glandular lobules. Partially, the isotransplants display the transformation of proliferation stage into that of cellular cytodifferentiation followed by gradual appearance of striated ducts, acini and even granular convoluted tubules on the 5th week after transplantation. Also the reoccurrence of enzyme activities in the transplant parenchyma after their initially total disappearance is testifying of both proliferation and cytodifferentiation developed gradually. During the first days of implantation, the revascularization of grafts occurs, those being high in AP endothelial activity of vessels newly formed. This is to conclude that higher proliferative intensity of isotransplants and their exclusive cytodifferentiation demonstrate that an undifferentiated murine SMG which can develop itself ontogenetically is more effective graft than a SMG differentiated fully. On the next stage, the development of glandular grafts will be studied with more delay after transplantations. Also the enzyme implementation of new parenchymatous components is to be elucidated. Further experimentation is planified as to influencing intracerebral SMG graft development with administration of hormones and isoproterenol to laboratory animals.
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PMID:[Regeneration of auto- and isografts of submandibular glands in the brain of laboratory mice. I. Morphologic evaluation of the healed graft using light microscopy]. 264 Mar 57

Renin granules were isolated from rat kidney cortex by a continuous polyvinyl-pyrrolidone-coated colloidal silica (Percoll) density gradient centrifugation. A major peak of renin activity was found at a density of 1.12-1.13 g/ml, and the specific activity of renin in the peak fraction was increased by approximately 70-fold, as compared with that in the kidney cortex homogenate. On the other hand, activities of other reference enzymes, such as succinate dehydrogenase, acid phosphatase and glucose-6-phosphatase, were not detectable in the peak fraction. When the extract of the peak fraction was applied to a pepstatin column, trypsin-activated renin could not be detected in the breakthrough fractions. These results indicate that renin granules of the rat kidney cortex contain only active renin.
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PMID:Renin granules isolated from rat kidney cortex by continuous colloidal silica (Percoll) density gradient centrifugation. 301 76

The effects of intermittent infusions of dobutamine were studied in young normal male subjects during a period of bedrest deconditioning to determine whether this synthetic catechol affects physical conditioning processes in humans. 24 volunteers were placed at bedrest and randomized to daily 2-h treatments of saline infusions (control), dobutamine infusions, or maintenance exercise (control). Exercise, hemodynamic, and metabolic studies were performed at base line and at the termination of the 3-wk treatment period. Maximal exercise (duration, oxygen consumption, and workload) fell for the saline group and remained unchanged for the dobutamine and exercise groups. Hemodynamics during exercise were maintained the same as pretreatment base line for the dobutamine and exercise groups, whereas stroke volume and cardiac output dropped and heart rate rose for the saline group. The metabolic profile showed an increased blood lactate response at rest and during submaximal exercise after 3 wk of bedrest for the saline group, and essentially no change for the exercise and the dobutamine groups. Extraction of oxygen across the exercising lower limb rose for the dobutamine group, as did the activity of the skeletal muscle oxidative enzymes, citrate synthetase, and succinate dehydrogenase. In contrast to the exercise control group, the saline and dobutamine groups developed orthostatic hypotension, tachycardia, and accentuation of the renin-aldosterone response over the 3-wk treatment period; for the saline group, this is best explained by the observed fall in blood volume and for the dobutamine group, by the blunting of vascular vasoconstrictive responses. During a period of bedrest deconditioning in humans, infusions of dobutamine maintain many of the physiologic expressions of physical conditioning.
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PMID:Prevention of bedrest-induced physical deconditioning by daily dobutamine infusions. Implications for drug-induced physical conditioning. 393 70

The subcellular distribution and nature of rat renal renin has been investigated by means of analytical subcellular fractionation and gel filtration on Sephadex G-100. During differential centrifugation, renin activity was recovered mainly in soluble and heavy mitochondrial fractions. On sucrose gradient centrifugation in either a conventional or in a B XIV zonal rotor, renin activity equilibrated at 1.54 M sucrose and was partially resolved from marker enzymes for mitochondria (succinate dehydrogenase), lysosomes (acid phosphatase), plasma membranes (alkaline phosphatase), and peroxisomes (catalase). On gel filtration of the soluble or extracts of the renin-granular fractions on Sephadex G-100, renin activity eluted as a single peak with an apparent molecular weight (MW) of 42,000; no change in activity was found when these fractions were acidified to pH 3.0. When kidney homogenates were prepared in the presence of the proteolytic inhibitor N-ethylmaleimide (NEM, 10 mM), whereas the renin from the granular fractions displayed a MW of 44,000, that from the soluble fraction was apparently higher (69,000). Addition of NEM (10 mM) to the soluble fraction previously shown to contain only the low MW form of renin also resulted in an apparently high MW form of renin. These results indicate that rat renal renin is associated with a mechanically fragile, distinct type of subcellular organelle. Renin within this structure is of the low MW form and is not acid activatable. The soluble fraction, however, contains a factor(s) that, in the presence of NEM, combines with the low MW renin to form a complex of apparently high MW.
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PMID:Subcellular distribution and storage form of rat renal renin. 699 67

The mechanisms and myocardial alterations associated with NO-deficient hypertension are still far from clear. The aim of the present study was to focus on the enzyme histochemical and subcellular changes in the heart of L-NAME treated rats, as well as to examine the influence of captopril treatment. Wistar rats were administered either L-NAME (40 mg/kg/day) alone or together with captopril (100 mg/kg/day) for a period of 4 weeks. A significant increase of blood pressure confirmed the reliability of the model. The results showed that long-lasting L-NAME administration was accompanied by a decrease of endothelial NO-synthase activity and by a significant local decrease of the following enzyme activities: capillary-related alkaline phosphatase, 5'-nucleotidase and ATPase (but not dipeptidyl peptidase IV) and cardiomyocyte-related glycogen phosphorylase, succinic dehydrogenase, beta-hydroxybutyrate dehydrogenase and ATPases. No activity of these enzymes was found in the scar, whereas a marked increase of alkaline phosphatase and dipeptidyl peptidase IV activities was found in the foci of fibrotization. Histochemical changes correlated with subcellular changes, which were characterized by 1) apparent fibroblast activation associated with interstitial/perivascular fibrosis, 2) heterogeneous population of the normal, hypertrophic and injured cardiomyocytes, 3) enhancement of the atrial granules and their translocation into the sarcolemma, and 4) impairment of capillaries as well as by induction of angiogenesis. Similar alterations were also found in the heart of captopril co-treated rats, despite of the significant suppression of blood pressure. The results indicate that NO-deficient hypertension is accompanied by metabolic disturbances and ultrastructural alterations of the heart and these changes are probably not induced by the renin-angiotension system only.
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PMID:Chronic disturbances in NO production results in histochemical and subcellular alterations of the rat heart. 1080 8

Monogenic or single-gene forms of human hypertension result from mutations involving regulatory elements of the renin-angiotensin-aldosterone system (RAAS) or occur in syndromes associated with hereditary pheochromocytoma. RAAS gain-of-function mutations result in sodium retention, suppression of plasma renin activity, and often, but not invariably, hypokalemia. Hereditary RAAS syndromes result from intrinsic renal abnormalities (apparent mineralocorticoid excess and Liddle's syndromes) or from mineralocorticoid excess states (congenital adrenal hyperplasia and glucocorticoid-remediable aldosteronism). In the hereditary pheochromocytoma syndromes many asymptomatic individuals are identified because they are at-risk individuals in kindreds with a pheochromocytoma-predisposing syndrome. On the other hand, up to 25% of subjects with presumed "sporadic" pheochromocytoma have germline mutations in one of four pheochromocytoma susceptibility genes (the RET proto-oncogene, von Hippel-Lindau gene, neurofibromatosis F1 gene, and succinate dehydrogenase subunit D and succinate dehydrogenase subunit B genes). Hereditary pheochromocytomas are typically intra-adrenal and bilateral and patients typically present at younger ages compared with sporadic pheochromocytoma.
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PMID:Screening for genetic causes of hypertension. 1241 72

Angiotensin II (Ang II) induces mitochondrial dysfunction. We tested whether Ang II alters the "metabolomic" profile. We harvested hearts from 8-week-old double transgenic rats harboring human renin and angiotensinogen genes (dTGRs) and controls (Sprague-Dawley), all with or without Ang II type 1 receptor (valsartan) blockade. We used gas chromatography coupled with time-of-flight mass spectrometry to detect 247 intermediary metabolites. We used a partial least-squares discriminate analysis and identified 112 metabolites that differed significantly after corrections (false discovery rate q <0.05). We found great differences in the use of fatty acids as an energy source, namely, decreased levels of octanoic, oleic, and linoleic acids in dTGR (all P<0.01). The increase in cardiac hypoxanthine levels in dTGRs suggested an increase in purine degradation, whereas other changes supported an increased ketogenic amino acid tyrosine level, causing energy production failure. The metabolomic profile of valsartan-treated dTGRs more closely resembled Sprague-Dawley rats than untreated dTGRs. Mitochondrial respiratory chain activity of cytochrome C oxidase was decreased in dTGRs, whereas complex I and complex II were unaltered. Mitochondria from dTGR hearts showed morphological alterations suggesting increased mitochondrial fusion. Cardiac expression of the redox-sensitive and the cardioprotective metabolic sensor sirtuin 1 was increased in dTGRs. Interestingly, valsartan changed the level of 33 metabolites and induced mitochondrial biogenesis in Sprague-Dawley rats. Thus, distinct patterns of cardiac substrate use in Ang II-induced cardiac hypertrophy are associated with mitochondrial dysfunction. The finding underscores the importance of Ang II in the regulation of mitochondrial biogenesis and cardiac metabolomics, even in healthy hearts.
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PMID:Metabolomics in angiotensin II-induced cardiac hypertrophy. 2006 48


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