Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heart and red blood cell endogenous antioxidant status and plasma lipids were investigated in hypertensive, 14-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats fed a standard commercial rat chow. Specific heart and red blood cell antioxidant enzyme activities, as well as the susceptibility of tissues to H2O2-induced glutathione (GSH) depletion and lipid peroxidation, were measured. Systolic blood pressure in SHR was greater than in WKY rats at 13 weeks of age (197 +/- 12 vs. 132 +/- 14 mmHg (1 mmHg = 133.3 Pa); p < or = 0.05), confirming the presence of hypertension in SHR. Red blood cell catalase (CAT) and superoxide dismutase (SOD) activities were greater (p < or = 0.05) in SHR than WKY rats. Red blood cell CAT activity was positively correlated (r = +0.634; p = 0.026) with SOD, which in turn was correlated (r = +0.709; p = 0.049) with systolic blood pressure. Heart SOD activity was higher (p < or = 0.05) in SHR, while glutathione reductase (GSSG-Red) activity was lower (p < or = 0.05) than in WKY rats. This reduced ability to recycle GSH in the heart coincided with greater (p < or = 0.05) levels of H2O2-induced lipid oxidation products in SHR. Plasma total cholesterol and triacylglycerol levels were lower (p < or = 0.05) in SHR than WKY rats, with no visible signs of atherosclerosis in either SHR or WKY rats. In summary, hypertension in SHR was associated with alterations in antioxidant enzyme profiles of red blood cells and heart, with the latter showing an increased susceptibility to in vitro lipid oxidation. Although hypertension is a recognized factor in the development of human atherosclerosis, spontaneously hypertensive rats did not exhibit signs of aortic plaque, reflecting the resistance of this species to the development of atherosclerosis.
 ...
PMID:Heart and red blood cell antioxidant status and plasma lipid levels in the spontaneously hypertensive and normotensive Wistar-Kyoto rat. 877 9

1. To determine biochemically the incipient timing of cerebral stroke in stroke-prone spontaneously hypertensive rats (SHRSP) the relation between the glutathione peroxidase (GSH-Px) activity in erythrocytes and the extent of stroke lesion was investigated. 2. When the blood pressure of SHRSP was maintained over 250 mmHg, the GSH-Px activity was lowered and the body weight also decreased. In the SHRSP where the GSH-Px activity in erythrocytes dropped below 23 units/mL blood, the incidence of cerebral stroke was 98% (n = 88/90). 3. The haemoglobin and haematocrit level were unchanged even after the GSH-Px activity dropped to 23 units/mL blood. 4. Lowering of GSH-Px activity in erythrocytes observed during continued hypertension was found to be due to decreased GSH-Px protein, but not to an inactivation of enzymes, as evidenced from immunochemical titration. 5. Lowering of GSH-Px activity in erythrocytes was found to be closely related with the incidence of cerebral stroke in SHRSP. These findings suggest that tracing of the GSH-Px activity in erythrocytes in SHRSP may serve as an indicator for prediction and prognosis of stroke lesion.
 ...
PMID:Relationship between erythrocytes glutathione peroxidase and incidence of stroke lesion in the stroke-prone spontaneously hypertensive rat. 907 38

In 14 patients (4 males and 10 females) with systemic hypertension plasma and erythrocyte lipid peroxides, plasma and erythrocyte catalase activity, plasma glutathione S-transferase (GST) activity, blood reduced glutathione (GSH) content and erythrocyte oxidant stress were investigated. All parameters were performed after clinical examination and then the patients were assigned to receive ACE inhibitor therapy, captopril (25-50 mg given twice per day) or enalapril (10-40 mg given twice per day). After six months the determination of lipid peroxides and antioxidative factors was repeated. At the beginning of the study both treated groups showed significantly higher plasma lipid peroxides compared to the control group. Both used ACE inhibitors produced significant decrease of plasma lipid peroxides after six months. Blood GSH content was also significantly higher in both patient groups before the treatment compared to the controls. Neither captopril nor enalapril produced any significant effect on GSH. Initial values of plasma GST activity in the patients were similar to the control group and did not significantly change after six month treatment. The patients assigned to receive enalapril showed significantly enhanced initial plasma catalase activity according to the controls. After six months treatment both ACE inhibitors significantly decreased plasma catalase activity. Erythrocyte lipid peroxides, erythrocyte catalase activity and oxidant stress of erythrocytes in both groups studied neither differ significantly at initial time of investigation according to the control group nor during or after six month treatment.
 ...
PMID:Changes of lipid peroxides and antioxidative factors levels in blood of patients treated with ACE inhibitors. 912 91

Effects of benidipine hydrochloride or triple therapy (hydralazine, reserpine, and hydrochlorothiazide) on renal cortical and medullary intrinsic antioxidant enzyme (AOE) activity were evaluated in stroke-prone spontaneously hypertensive rats (SHR-SP) as an animal model for human essential hypertension with cerebral stroke. This study showed a significant decrease of renal intrinsic glutathione peroxidase (GSH-Px) activity in untreated SHR-SP. Renal GSH-Px activity in untreated SHR-SP was significantly lower than that in Wister Kyoto rats (WKY) as a normotensive reference strain. GSH-Px activity in SHR-SP was significantly improved after benidipine hydrochloride therapy. Levels of urinary albumin excretion or creatinine clearance (Ccr) in SHR-SP were also improved after the therapy. Glomerular sclerosis index was slightly improved in SHR-SP treated with benidipine hydrochloride according to light microscopic analysis. It appears that hypertension may influence the renal intrinsic GSH-Px activity, albuminuria, and Ccr in SHR-SP. Thus it is indicated that control of blood pressure may improve the GSH-Px activity in SHR-SP.
 ...
PMID:Effects of benidipine hydrochloride on antioxidant enzyme activity in stroke-prone spontaneous hypertensive rats (SHR-SP). 913 5

In 10 women with disturbed pregnancies without hypertension, reduced (GSH) and oxidized glutathione (GSSG) as well as lipid peroxides as thiobarbituric acid reactive substances (TBARS) were determined in the placenta and in the uterine tissue after unexpected stress-induced Caesarian section (group II). Production of TBARS was also measured in vitro in the 9000 x g supernatant of both tissues. The results were compared with those from women after normal pregnancy and expected Caesarian section (group I). After normal pregnancy higher TBARS and lower GSH with higher GSSG/GSH ratio were found in the placenta in comparison to the uterine tissue, indicating an oxidant/antioxidant imbalance in the placenta. No statistically significant differences were shown between the parameters of groups I and II. The possible oxidant stress associated with disturbed pregnancy and subsequent unexpected Caesarian section in this study was insufficient to alter tissue levels of glutathione nor the peroxidative status of placenta and uterus.
 ...
PMID:Peroxidative and glutathione status in uterus and placenta after normal and pathological pregnancy. 949 53

To study the mechanism of the fall of glutathione peroxidase (GSH-Px) activity in erythrocyte after cerebral strokes in stroke-prone spontaneously hypertensive rats (SHRSP), erythrocytes were fractionated into low density erythrocytes (LD-E) and high density erythrocytes (HD-E) by a density gradient centrifugal method using Percoll solution, and fluctuation of the distribution ratio and changes of GSH-Px activity in fractionated erythrocytes were investigated. The distribution ratio of LD-E and HD-E in erythrocytes of SHRSP was about 4:1 at 5 weeks of age (n = 6), and the distribution to HD-E increased along with aging. While the distribution ratio was changed, however, there was no change in the GSH-Px activity in both LD-E and HD-E of erythrocytes. In senile, 30-week-old SHRSP (n = 4) with advanced hypertension, the GSH-Px activity in the HD-E was lower, in proportion to the increase of the distribution rate against HD-E. On the other hand, in SHRSP (n = 5) having cerebral stroke, the distribution ratio of LD-E and HD-E was about 1:4. The GSH-Px activity was 31.4 +/- 2.9 units/10(10) erythrocytes in LD-E, which was hardly different from the value of SHRSP without stroke (35.7 +/- 3.3 units/10(10) erythrocytes). In HD-E, however, the activity was 18.2 +/- 2.2 units/10(10) erythrocytes, being lower than the activity of SHRSP without stroke. At the moment when the GSH-Px activity had dropped to 17 units/mg hemoglobin, and the control diet was changed to one based on fish or a hydralazine treatment given, the activity recovered, and an increase in body weight and the distribution rate of the LD-E over HD-E was increased. It is clear from these experiments that the fall of erythrocyte GSH-Px activity observed after cerebral stroke is due to a decrease of LD-E and increase of HD-E, which has lowered activity. However, nothing definite is known on the relationship between the fall of GSH-Px activity in erythrocytes and disorder in cerebral tissue. It appears that the fall of the GSH-Px activity causes at least functional and structural changes in erythrocytes, which interfere with the delivery of oxygen to peripheral tissues, triggering oxidation stress in cerebral tissues.
 ...
PMID:Cell age distribution of erythrocytes at the incidence of cerebral stroke in stroke-prone spontaneously hypertensive rats, and their glutathione peroxidase activity. 957 77

Plasma and lipoprotein lipid composition and endogenous hepatic antioxidant status were investigated in hypertensive, 14-week-old spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats fed a standard commercial rat chow. Total plasma calcium and magnesium concentrations were similar between both rat strains; however, systolic blood pressure in SHR was greater than in WKY at 13 weeks of age (197 +/- 12 vs. 132 +/- 14 mmHg; p < or = 0.05), confirming hypertension in SHR. Total plasma cholesterol and triacylglycerol concentrations were lower (p < or = 0.05) in SHR compared with WKY. A lower (p < 0.05) HDL cholesterol level in SHR plasma resulted in a higher LDL to HDL cholesterol ratio compared with WKY counterparts. No significant differences in the relative proportion of HDL apolipoprotein A-I fraction were observed between SHR and WKY. Both SHR VLDL and HDL triacylglycerol fractions were lower (p < 0.05) in SHR than WKY. Analysis of liver antioxidant enzyme activities showed no differences in rat liver superoxide dismutase (SOD), but lower (p < 0.05) liver glutathione peroxidase (GSH-Px) activity in SHR. However, liver glutathione (GSH) levels were similar in SHR and WKY counterparts. A possible compensatory effect to the oxidative status of SHR was suggested by the significant (p < 0.05) increase in both liver catalase (CAT) and glutathione reductase (GSSG-Red) activities. Despite these results, in vitro oxidative challenge studies with H2O2 demonstrated a greater susceptibility of liver to GSH depletion in the SHR, although no parallel change in thiobarbituric acid reactive substances (TBARS) production was observed. The comparatively lower plasma cholesterol observed in hypertensive SHR paralleled specific differences in liver catalase and glutathione redox antioxidant enzyme activities.
 ...
PMID:Plasma and lipoprotein lipid composition and hepatic antioxidant status in spontaneously hypertensive (SHR) and normotensive (WKY) rats. 963 61

This study is aimed at examining whether essential arterial hypertension (HTN) or ACE inhibitors have any effect on erythrocyte selenium (Se)-dependent and Se-non-dependent glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activity. Eleven patients with HTN (2 men and 9 women) and 9 healthy volunteers were included in this study after clinical examination and laboratory investigation. The activities of all three enzymes were determined and then the patients were assigned to receive ACE inhibitor therapy consisting of captopril, 25 to 50 mg daily, or enalapril, 10 to 40 mg daily. After 1 year, the determination of antioxidant enzymes was repeated. Our results showed that the initial values of Se-dependent GSH-Px in patients treated with ACE inhibitors were significantly lower (19.60 +/- 3.50 microM NADPH/min(-1)/mgHb(-1)) compared with the controls (28.64 +/- 4.93 microM NADPH/min(-1)/mgHb(-1); p < 0.001), whereas the activity of Se-non-dependent GSH-Px was significantly enhanced (13.55 +/- 1.46 microM NADPH/min(-1)/mgHb(-1); p < 0.001) compared with the control group (9.44 +/- 0.81 microM NADPH/min(-1)/mgHb(-1); p < 0.001). ACE inhibitors did not significantly change the activity of Se-dependent GSH-Px or Se-non-dependent GSH-Px. No significant alteration was observed in SOD activity.
 ...
PMID:Selenium-dependent GSH-Px in erythrocytes of patients with hypertension treated with ACE inhibitors. 972 2

The purpose of this study was to examine the relationship between arterial hypertension (HTN), chronic heart disease (CHD), and selenium (Se) status. Blood and plasma Se concentrations and Se-dependent GSH-Px activities were determined in 40 patients (HTN = 20; CHD = 20) and 17 healthy volunteers aged 41 to 66 years. Whole blood and plasma Se concentrations were significantly lower in the patients with HTN (19.1% and 26.3%, respectively) and CHD (33.1% and 29.4%, respectively) compared with the values obtained in the controls. The hypertensive patients had lower plasma Se-GSH-Px (26.7%), and those with CHD had both lower whole blood (19.5%) and plasma Se-GSH-Px activities (30.2%). A significant positive correlation between plasma Se-GSH-Px activity and ejection fraction (EF) was found in patients with CHD. There were significant correlations between plasma and whole blood Se concentration, plasma Se concentration and Se-GSH-Px activity, and whole blood Se and Se-GSH-Px activity. Our results showed that hypertensive patients and those with CHD had lower Se levels compared with controls. We conclude that low Se content might be a risk factor for development of HTN and CHD.
 ...
PMID:Blood and plasma selenium levels and GSH-Px activities in patients with arterial hypertension and chronic heart disease. 972 4

The effects of varying dietary fat saturation [butter (B), beef tallow (BT)] or polyunsaturation [(n-6) soybean oil (SBO), (n-3) menhaden oil (MO)] and cholesterol content (0.05 and 0.5 g/100 g) on systolic blood pressure (SBP), plasma lipids and tissue antioxidant status were investigated in 14-wk-old spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats. Varying dietary fat composition for 9 wk had no influence on SBP in either SHR or WKY rats. Rats fed MO diets exhibited smaller (P < 0.05) body weight gains, lower (P < 0.05) feed efficiency ratios and lower (P < 0.05) plasma cholesterol concentrations than those fed the B, BT and SBO diets. Significant (P < 0.05) interactions for animal strain x cholesterol intake and animal strain x fat source were noted for serum cholesterol concentrations. SHR exhibited higher (P < 0.05) RBC and liver catalase (CAT), and heart and liver superoxide dismutase (SOD) activities similar to those of WKY rats. The lower (P <0.01) RBC, heart and liver glutathione peroxidase (GSH-Px) activities observed in SHR coincided with higher (P <0.01) glutathione reductase (GSSG-Red), compared with WKY rats. Dietary cholesterol intake had no effect on RBC, heart and liver total sulfhydryl concentration or GSH-Px activities, but increased (P <0. 001) liver GSSG-Red. Feeding MO resulted in lower (P <0.001) RBC and heart GSH-Px activities. In contrast, feeding B and BT resulted in lower GSH-Px in liver. The significant (P < 0.01) animal strain x fat source interaction obtained for liver GSH-Px activity indicated that SHR responded differently to polyunsaturated fatty acid feeding than their WKY counterparts. Diet-induced changes in tissue antioxidant status were tissue specific and did not affect the development of hypertension in SHR.
 ...
PMID:Variations in dietary fat and cholesterol intakes modify antioxidant status of SHR and WKY rats. 977 27


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>