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Hypertensive Subjects (hypertensive + subject)
Selected AbstractsShort-term cortisol infusion in the brachial artery, with and without inhibiting 11,-hydroxysteroid dehydrogenase, does not alter forearm vascular resistance in normotensive and hypertensive subjectsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2002S. H. M. Van Uum Abstract Background Vascular tone is increased in primary hypertension, and glucocorticoids affect vascular tone. Local cortisol availability is modulated by activity of 11,-hydroxysteroid dehydrogenase (11,-HSD). As this activity may be decreased in patients with primary hypertension, vascular sensitivity to cortisol may be increased in these patients. We studied the acute effect of cortisol on forearm vascular resistance (FVR) by infusing cortisol directly into the brachial artery, both with and without inhibition of 11,-HSD, in normotensive and hypertensive subjects. Design Twenty normotensive volunteers and 20 patients with primary hypertension participated in the study. After a 10-min infusion of vehicle (glucose 5%), cortisol was infused into the brachial artery in three stepwise increasing doses (3·5, 10·5 and 35 µg per 100 mL of forearm volume), each for 10 min. Next, the participants received placebo or 500 mg glycyrrhetinic acid (GA) orally, and 150 min later the same infusion schedule was repeated. Forearm vascular resistance was measured during the last 5 min of the infused vehicle and of each dose. Arterial and forearm venous plasma samples for measurement of cortisol and cortisone were taken at the end of the infusions of glucose 5% and the highest cortisol dose. Results In both normotensive and hypertensive subjects, neither the infusion of cortisol nor the administration of GA changed FVR. Also 2 h after the cortisol infusion there remained no change in FVR in both the normotensive and hypertensive groups who received placebo. Following the infusion of the highest cortisol dose, total plasma cortisone levels in the venous plasma were decreased compared with levels in the arterial plasma (36 ± 3 and 49 ± 4 nmol L,1, respectively, P < 0·05). The protein-bound venous cortisone was 37·1 ± 4·8 nmol L,1 during the vehicle compared with 23·9 ± 3·7 nmol L,1 during the cortisol infusion (P < 0·01), whereas the free cortisone level was not altered by the cortisol infusion. Conclusions In both normotensive and hypertensive subjects, high-dose cortisol infusion both with and without 11,-HSD inhibition did not change FVR either immediately or after 2 h. We could not demonstrate in vivo 11,-HSD activity in the forearm vascular tissues. When binding of cortisone to CBG is changed, e.g. during cortisol infusion, arterio-venous changes in cortisone cannot reliably be used to assess (alterations in) local 11,-HSD activity. [source] Irbesartan has no short-term effect on insulin resistance in hypertensive patients with additional cardiometabolic risk factors (i-RESPOND)INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2010K. G. Parhofer Summary Aims:, Intervention studies have shown that angiotensin receptor blockers (ARB) may reduce the incidence of type 2 diabetes mellitus. It is currently unclear whether short-term therapy with ARBs affects metabolic parameters. Methods:, i-RESPOND, a randomised, controlled, multicentre, double-blind study evaluated the effect of 16 weeks of irbesartan vs. hydrochlorothiazide (HCTZ) on insulin resistance as well as on lipid and inflammatory parameters in hypertensive subjects with metabolic syndrome. Patients received irbesartan (150 mg/d; n = 211) or HCTZ (12.5 mg/d; n = 215), titrated to 300 mg/day and 25 mg/day respectively. In a second part of the study (weeks 16,28), patients initially randomised to irbesartan received additional HCTZ and vice versa. Results:, At week 16 both irbesartan and HCTZ had no effect on insulin resistance measured by the Matzuda index and beta-cell function. Similarly, in the second part of the study (week 16,28) no differences between irbesartan and HCTZ with respect to glucose metabolism were observed. However, irbesartan induced beneficial changes in high-sensitivity-C-reactive protein (hs-CRP) (irbesartan: ,5.5 ± 5.2%; HCTZ + 19.9 ± 6.5%, p = 0.0024) and in urinary albumin/creatinine ratio (ACR) (irbesartan: ,13%; HCTZ + 9%; p = 0.0041) compared with HCTZ despite a similar decrease in blood pressure in both treatment groups. Irbesartan and HCTZ were well tolerated and adverse events were comparable. Conclusion:, Irbesartan did not show significant favourable effects on insulin resistance compared with HCTZ in this study; however, may have beneficial effects on inflammation and microalbuminuria in hypertensive patients with metabolic syndrome. [source] Comparison between three-dimensional volume-selective turbo spin-echo imaging and two-dimensional ultrasound for assessing carotid artery structure and functionJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2005Lindsey A. Crowe PhD Abstract Purpose To compare a volume-selective three-dimensional turbo spin echo (TSE) technique with ultrasound (US) for assessing carotid artery wall structure and function. Materials and Methods A three-dimensional volume-selective TSE technique was used to image the carotid artery in 10 healthy subjects and five hypertensive subjects (each of whom were scanned three times while they received different hypertension treatments). Lumen and wall area were measured on MR images. Two-dimensional US measurements of the intima-media thickness (IMT) and lumen diameter were taken in three orientations through a single cross section. The lumen area change over the cardiac cycle was used to determine distension. For validation, a Bland-Altman analysis was used to compare the vessel wall and lumen areas measured by three-dimensional MRI volumes with those obtained by US scans. Results Agreement between the two methods was found. The mean difference in distension between US and MRI was 1.2% (±5.1%). For the wall area measurements, good agreement was shown, but there was a systematic difference due to the visualization of the adventitia by MRI. Both techniques offer an easy way to objectively measure lumen indices. MRI can provide the complete circumference over the length of a vessel, while US is flexible and relatively inexpensive. The application of US is limited, however, when subjects are poorly echogenic. A difference between hypertensive and healthy subjects was found. Conclusion There was a good agreement between MRI and the clinically established two-dimensional US method. The MRI method has the advantage of providing increased vessel coverage, which permits one to assess localized abnormalities without assuming vessel uniformity. J. Magn. Reson. Imaging 2005;21:282,289. © 2005 Wiley-Liss, Inc. [source] Effects of Alcohol Withdrawal on 24 Hour Ambulatory Blood Pressure Among Alcohol-Dependent PatientsALCOHOLISM, Issue 12 2003Ramón Estruch Background: Although epidemiologic studies have reported an association between alcohol intake and high blood pressure (BP), the results of intervention studies have shown inconsistent results. We embarked on a study to determine whether different subgroups of alcohol-dependent patients may be identified in relation to the effect of alcohol on BP. Methods: Fifty alcohol-dependent men (mean age, 41.4 years) received 0.4 g of ethanol per kilogram of body weight every 4 hr in 200 ml of orange juice during 24 hr and the same amount of orange juice without ethanol during another 24 hr. Twenty-four hour ambulatory BP monitoring was performed during ethanol and orange juice intakes, as was hormonal and biochemical analysis. Results: Thirty-five (75%) alcohol-dependent men were normotensive and 15 (30%) hypertensive. Eighteen (51%) normotensive and 12 (80%) hypertensive subjects showed a significant decrease in 24 hr mean BP after ethanol withdrawal (mean decrease of 8.4 mm Hg [95% confidence interval, ,11.2 to ,5.7] and 12.5 mm Hg [confidence interval, ,16.2 to ,8.8], respectively) and were considered as sensitive to alcohol. The remaining alcohol-dependent subjects were considered as resistant to alcohol. Normotensive subjects sensitive to ethanol showed a significantly greater left ventricular mass and a significantly lower ejection fraction than those normotensive patients whose BP did not change after ethanol withdrawal (both p < 0.01). Conclusions: More than three fourths of the hypertensive and more than half of the normotensive alcohol-dependent patients showed sensitivity to the pressor effects of ethanol. Impairment also was observed in heart function in normotensive patients sensitive to the pressor effects of ethanol. [source] Spontaneous Feline Hypertension: Clinical and Echocardiographic Abnormalities, and Survival RateJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2003Valerie Chetboul Systemic hypertension was diagnosed in 58 of 188 untreated cats referred for evaluation of suspected hypertension-associated ocular, neurologic, cardiorespiratory, and urinary disease, or diseases frequently associated with hypertension (hyperthyroidism and chronic renal failure). Hypertensive cats were significantly older than normotensive subjects (13.0 ± 3.5 years versus 9.6 ± 5.0 years; P < .01), and had a greater prevalence of retinal lesions (48 versus 3%; P < .001), gallop rhythm (16 versus 0%; P < .001), and polyuria-polydipsia (53 versus 29%; P < .01). Blood pressure was significantly higher (P < .001) in cats with retinopathies (262 ± 34 mm Hg) than in other hypertensive animals (221 ± 34 mm Hg). Hypertensive cats had a thicker interventricular septum (5.8 ± 1.7 versus 3.7 ± 0.64 mm; P < .001) and left ventricular free wall (6.2 ± 1.6 versus 4.1 ± 0.51 mm; P < .001) and a reduced diastolic left ventricular internal diameter (13.5 ± 3.2 versus 15.8 ± 0.72 mm; P < .001) than control cats. Left ventricular geometry was abnormal in 33 of 39 hypertensive subjects. No significant difference was found in age or blood pressure at the initial visit between cats that died or survived over a 9-month period after initial diagnosis of hypertension. Mean survival times were not significantly different between hypertensive cats with normal and abnormal left ventricular patterns. Further prospective studies are needed to clearly identify the factors involved in survival time in hypertensive cats. [source] Hypercapnic acidosis and compensated hypercapnia in control and pulmonary hypertensive piglets,PEDIATRIC PULMONOLOGY, Issue 2 2003K. Jane Lee MD Abstract Low tidal volume/inspiratory pressure ventilator strategies result in hypercapnia, which has been shown to increase pulmonary vasomotor tone. This may be particularly detrimental in infants and children with preexistent pulmonary hypertension. In this study, a piglet model of chronic hypoxia-induced pulmonary hypertension was used to test the hypotheses that: 1) the effects of hypercapnic acidosis are exaggerated by preexistent pulmonary hypertension; and 2) the pulmonary hemodynamic effects of hypercapnic acidosis are attenuated by normalizing pH. Pulmonary hypertension was induced by 2 weeks of hypoxia. Hemodynamic responses were measured in control and pulmonary hypertensive piglets during both normoxia and hypoxia under normocapnic, hypercapnic acidotic, and compensated hypercapnic conditions. We found that: 1) hypercapnic acidosis increased both normoxic and hypoxic pulmonary vascular resistance index (PVRI) in control piglets; 2) the pressor effects of hypercapnia were not attenuated by infusing bicarbonate to normalize the pH; and 3) piglets with chronic hypoxia-induced pulmonary hypertension had elevated baseline normoxic and hypoxic PVRI, but responded to hypercapnic acidosis and compensated hypercapnia in a similar way to control piglets. These data suggest that acute hypercapnic acidosis may have deleterious effects on the pulmonary hemodynamics of normal and pulmonary hypertensive subjects which may not be acutely reversed by buffering the pH. Pediatr Pulmonol. 2003; 36:94,101. © 2003 Wiley-Liss, Inc. [source] Panax notoginseng (Burk.) effects on fibrinogen and lipid plasma level in rats fed on a high-fat dietPHYTOTHERAPY RESEARCH, Issue 2 2003A. F. G. Cicero Abstract Several studies have shown that notoginsenoides improve diastolic function in hypertensive subjects, induce the fibrinolytic system in in vitro models and act as antiproliferative agents on vessel leiomyocytes. Our aim was to evaluate their effect on fibrinogen and lipid plasma levels compared with a well-known HMGCoA reductase inhibitor. Seventy Wistar male adult rats on a fat-enriched diet were treated orally with P. notoginseng pulverized root (43,mg/kg/day or 86,mg/kg/day; 20 animals per group), fluvastatin (3,mg/kg/day; 20 animals) or physiological saline (5,mL/kg/day; 10 animals). The ten rats on a normocaloric diet were also treated with 5,mL/kg/day of physiological saline. After a 28-day treatment, the rats were killed and their blood analysed with standard procedures. Treatment with 43,mg/kg/day of P. notoginseng or 3,mg/kg/day of fluvastatin showed similar activity in decreasing total cholesterol (,23.70%, ,19.29%, respectively) and triglycerides (,21.59%, ,18.55%). The most evident effect of P. notoginseng was the reduction of fibrinogenaemia in treated rats compared with the control values (,38.10%; p,<,0.001), no dose-relationship being shown in this effect. Moreover, no significant variation in HDL cholesterol and glucose levels was observed nor did relevant behavioural changes occur in association with the root intake. Besides a moderate, non dose-related decrease in the plasma lipid levels, P. notoginseng appeared to induce a significant reduction in the rat fibrinogenaemia. Copyright © 2003 John Wiley & Sons, Ltd. [source] Association of a polymorphism at the 5,-region of the angiotensin II type 1 receptor with hypertensionANNALS OF HUMAN GENETICS, Issue 3 2000N. TAKAHASHI Molecular variants of individual components of the renin-angiotensin system are thought to contribute to inherited predisposition towards essential hypertension. Using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and sequence analysis, we identified seven polymorphisms in the 5,-flanking region of the angiotensin II type 1 receptor (AGTR1/AT1) gene. We conducted a case-control study in a sample from the Japanese population to determine whether polymorphic markers in the 5,-flanking region of the AT1gene were associated with essential hypertension. The study compared 149 hypertensive subjects to 156 normotensive control subjects. A significantly higher frequency of the AT1(,535)*T allele was observed in hypertensive subjects. Evidence was obtained that the AT1(,535)*T allele showed a synergistic effect on risk of hypertension with angiotensin I converting enzyme D allele (ACE*D). [source] Plasma P-selectin is elevated in the first trimester in women who subsequently develop pre-eclampsiaBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 7 2001P.M. Bosio Objective To report plasma concentrations of the adhesion cell molecule P-selectin during pregnancy to determine the effect of subsequent development of hypertension and pre-eclampsia. Design A longitudinal study. Methods A longitudinal study involving 70 women followed up from early pregnancy; 20 who subsequently developed pre-eclampsia were compared with 24 who developed gestational hypertension and 26 normotensive women with normal obstetric outcome. The determination of citrate plasma soluble P-selectin levels throughout pregnancy was performed using a commercial quantitative sandwich immunoassay kit. The temporal course of plasma P-selectin in the three groups of subjects was analysed. Results There was no significant difference in mean plasma P-selectin concentration between normotensive and gestational hypertensive subjects at any stage of pregnancy. Using a cutoff level of 60 ng/mL, P-selectin concentration at 10,14 weeks had a negative predictive value for pre-eclampsia of almost 99%. Mean plasma P-selectin concentrations were significantly elevated by 10,14 weeks in women who later developed pre-eclampsia (P<0.001). Conclusions Our data support an inflammatory model for pre-eclampsia whereby endothelial cell activation may be secondary to a primary inflammatory response. Plasma P-selectin has significant potential as a first trimester clinical marker of pre-eclampsia. [source] Diagnostic ability of GDx VCC to discriminate between healthy eyes, ocular hypertensive subjects and glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2007E BORQUE Purpose: To evaluate the diagnostic ability of laser polarimeter GDx VCC to discriminate between healthy eyes, ocular hypertensive subjects and glaucoma patients. Methods: 417 eyes of 417 subjects were included. They were divided into 60 healthy controls, 289 ocular hypertensive subjects and 71 glaucoma patients. The GDx VCC parameters were compared among the study groups using analysis of variance. The receiver operating characteristic (ROC) curves were plotted for TSNIT average, superior average, inferior average, TSNIT standard deviation and nerve fiber indicator (NFI) between control and glaucoma eyes. Results: All evaluated parameters of the GDx VCC showed significant differences between control and glaucomatous eyes and between ocular hypertensive eyes and glaucoma patients. NFI had the greatest area under the ROC curve (AUC=0.881). The AUCs for the inferior average, TSNIT standard deviation and TSNIT average were 0,834, 0.824 and 0.819, respectively. NFI presented a larger AUC than the other GDx VCC parameters. Conclusions: The GDx VCC exhibited a good diagnostic ability to discriminate between healthy and glaucomatous eyes with damage in SAP. The best parameter was NFI. [source] Experimental and clinical study of the combined effect of arterial stiffness and heart rate on pulse pressure: Differences between central and peripheral arteriesCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2005Theodoros G Papaioannou SUMMARY 1.,Pulse pressure (PP) constitutes an independent predictor of cardiovascular events and mortality in various populations. Heart rate (HR) and arterial stiffness, in addition to their independent predictive value for cardiovascular complications, seem to interact with regard to the modification of PP. The aim of the present study was to investigate the association of PP with HR under different levels of arterial compliance (AC), revealing their synergistic effects. 2.,Seventy-one normotensive and untreated hypertensive subjects were examined. Arterial compliance was measured by the ,area' method, whereas central blood pressures and wave reflections were evaluated using the Sphygmocor® system (AtCor Medical, Sydney, NSW, Australia). A hydraulic Windkessel model was also used to evaluate the independent effect of HR and AC on PP. Peripheral PP was associated only with mean pressure and AC. In contrast, central PP was further related to HR (20 b.p.m. decrease in HR resulted in central PP augmentation by 5.6 mmHg) regardless of mean pressure, stroke volume, age and gender. However, this association was statistically significant only for subjects with lower AC (< 1.1 mL/mmHg) and not for those with more compliant arteries. These findings are also in accordance with the experimental data. 3.,Aortic PP is affected to a greater degree by HR changes compared with peripheral PP. This response was observed only at high levels of arterial stiffness. 4.,The present study provides the first evidence regarding the combined effect of AC and HR on aortic PP, which may lead to larger clinical or epidemiological studies aiming to optimization of drug treatment and to a possible reduction of cardiovascular risk. [source] | ||||||||||||||||||||||