Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a double-blind, double-dummy, placebo-controlled crossover design, the renal hemodynamic and tubular effects of 2-month specific vasodilation with a converting enzyme inhibitor (enalapril, 40 mg once daily) was compared with that of a calcium antagonist (verapamil slow release, 240 mg twice daily) in 15 patients with established essential hypertension. Enalapril and verapamil treatment induced a 9% reduction in mean blood pressure (BP). Heart rate (HR) was similar after placebo (66 beats/min), enalapril (63 beats/min), and verapamil (63 beats/min). Plasma norepinephrine (P-NE) was unaltered after enalapril and verapamil as compared with placebo (0.92, 0.88, and 1.33 nM, respectively). Plasma angiotensin II and aldosterone decreased and plasma renin activity (PRA) increased after enalapril but were unaltered after verapamil. Glomerular filtration rate (51Cr-EDTA) was not altered by either enalapril or verapamil, whereas renal blood flow (125I-hippurate) was reduced 9% by verapamil. Renal vascular resistance (RVR) was unchanged after enalapril as well as verapamil. Fractional excretion of electrolytes and diuresis were unaltered and body weight was similar after enalapril, verapamil, and placebo (81.0, 82.5, and 80.2 kg, respectively). Long-term treatment with enalapril and verapamil had a comparable antihypertensive effect. Neither enalapril nor verapamil appeared to induce reflex activation of the sympathetic nervous system. Renal hemodynamic and tubular function was well preserved with both drugs without signs of sodium and water retention.
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PMID:Renal and endocrine effects of long-term converting enzyme inhibition as compared with calcium antagonism in essential hypertension. 169 57

Split intrarenal hemodynamics in stenotic and contralateral kidneys of unilateral renovascular hypertension (RVH) were estimated by Gomez's formulae. Forty patients with essential hypertension and 40 patients with RVH were studied. Split para-amino hippurate and inulin clearances were measured by ureteral catheterization as indexes for effective renal plasma flow and glomerular filtration rates, allowing the estimation of intrarenal hemodynamics such as afferent arteriolar resistance (RA), efferent arteriolar resistance (RE) and glomerular hydrostatic pressure (PG) in each kidney. Normal values of intrarenal hemodynamic parameters were obtained in 24 normotensive subjects without ureteral catheterization, assuming each kidney had the half function of both kidneys. Systemic mean arterial pressure did not differ between essential and renovascular hypertension (141 +/- 3 vs. 148 +/- 3 mm Hg). Effective renal plasma flow and glomerular filtration rates were decreased in the stenotic kidney of RVH (98 +/- 8, 24 +/- 2 ml/min/m2), while increased in the contralateral kidney (195 +/- 11, 48 +/- 2), compared with the right kidney of essential hypertension (162 +/- 8, 33 +/- 1). Although effective renal plasma flow rate was not different from normal (191 +/- 8), glomerular filtration rate was significantly higher in the contralateral kidney of RVH than in normal (38 +/- 1). RA was elevated due to the stenotic lesion in the stenotic kidney (28,500 +/- 1,900 dyns.sec.cm-5), while the elevation in the contralateral kidney (10,800 +/- 600) was less than in the right kidney of essential hypertension (14,900 +/- 1,200). RE (5,800 +/- 300) in both kidneys of RVH was higher than in the right kidney of essential hypertension (4,500 +/- 200).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Glomerular hypertension in renovascular hypertensive patients. 206 13

We administered diltiazem HCl i.v. (0.05 mg/kg in bolus followed by 0.01 mg/kg/min for 45 min), and determined the changes in blood pressure (BP), glomerular filtration rate (GFR), renal blood flow (RBF), total renal resistance, urinary volume (UV), urinary sodium (UNa) and potassium excretion, urea and osmolar clearance, and tubular reabsorption ratio of sodium (TRNa%). The serum concentration of diltiazem achieved was similar to the maximum level after a single oral dose of 120 mg. GFR and RBF were measured by i.v. infusion of sodium thiosulfate and sodium rho-amino-hippurate, respectively, as indicators. The subjects included 12 cases of essential hypertension (EH), 10 of chronic glomerular nephritis (CGN) with hypertension, 12 of CGN without hypertension, 12 of ischemic heart disease (IHD), and 10 of normotensive controls. BP decreased in hypertensives but not in normotensives. In patients with EH, GFR and RBF increased markedly (by 25.3 +/- 33.8% and 30.7 +/- 39.5%, respectively). In patients with IHD, GFR increased slightly by 9.8 +/- 17.6%, whereas in patients with CGN with hypertension, GFR decreased by -4.3 +/- 14.3%. No significant change of these indices was observed in normal subjects and in patients with CGN without hypertension. UV and UNa increased and TRNa% decreased in all groups. Urea and osmolar clearance increased in almost every group.
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PMID:Clinical effects of intravenous diltiazem hydrochloride on renal hemodynamics. 243 98

Twenty-three men with essential hypertension participated in a double-blind placebo-controlled study with a crossover design to evaluate the long-term (nine weeks) effects of isradipine on central and renal hemodynamics. Isradipine as monotherapy was titrated from 2.5 to 5 and then to 7.5 mg twice daily. At the end of the crossover periods, cardiac output (dye-dilution) and intraarterial blood pressure were assessed. Compared with placebo, isradipine reduced ambulatory blood pressure from 174/104 to 154/91 (p less than 0.001), whereas the heart rate was unchanged. The reduction of blood pressure was entirely due to a reduction (36 percent; p less than 0.001) of the peripheral resistance. The baroreceptor sensitivity did not change (RR intervals during infusion of phenylephrine) but, with isradipine, the setpoint was shifted to lower blood pressure levels. Renal plasma flow (para-amino hippurate clearance) increased (465 versus 391 ml/minute; p less than 0.05), but glomerular filtration rate ([51Cr]ethylenediaminetetraacetic acid clearance) did not change. Hence, the filtration fraction decreased. With isradipine, there was a post-dose increase in natriuresis (0.45 to 0.34 mmol/minute; p = 0.06). Side effects were mild.
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PMID:Renal and hemodynamic effects of isradipine in essential hypertension. 252 57

Systemic and renal hemodynamics including split renal function tests were studied in 41 patients with renovascular hypertension (RVH) related to unilateral stenosis of main renal artery in comparison to 36 subjects with essential hypertension (EH). The two populations were matched for age, sex, body surface area, and systemic arterial pressure. Cardiac output and total peripheral resistances were similar in both groups, with total peripheral resistances increased in comparison to normal values (P less than .001). Patients with EH had a decreased blood volume (P less than .01) with a normal cardiopulmonary blood volume. Patients with RVH had a normal blood volume with an increase in cardiopulmonary blood volume (P less than .02). The para-amino hippurate clearance (CPAH) was decreased in EH. The decrease was similar in the right (160.3 +/- 56.9 mL/min/m2) and left kidneys (158.7 +/- 45 mL/min/m2). The inulin clearance (Cin) was similar in both kidneys (35.2 +/- 12.5 v 33.6 +/- 11.6 mL/min/m2). In addition, in EH, CPAH was negatively correlated with blood pressure (P less than .01). In patients with RVH, CPAH of the "stenotic" kidney was reduced (91.5 +/- 47.8 mL/min/m2) as well as Cin (22.9 +/- 9.3 mL/min/m2). In contrast a significant increase in CPAH (194.1 +/- 63.8 mL/min/m2) and Cin (47.6 +/- 12.6 mL/min/m2) was observed in the contralateral kidney. Kidney function (CPAH and Cin) was not correlated with blood pressure in the "stenotic" kidney. The CPAH and Cin of the nonstenotic kidney were positively and significantly correlated with systemic arterial pressure (P less than .001). The Cin was positively correlated with CPAH in all kidneys in RVH or in EH.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal hemodynamics in patients with sustained essential hypertension and in patients with unilateral stenosis of the renal artery. 270 91

Enalapril (at a mean dose of 25 mg), a potent, long-acting angiotensin converting enzyme inhibitor, was prescribed in combination with hydrochlorothiazide (at a mean dose of 64 mg) for 96 weeks in 11 patients with essential hypertension who had pretreatment (placebo) glomerular filtration rates of less than 80 ml/minute/1.73 m2. Blood pressure was well controlled. After 56 weeks of therapy, glomerular filtration rate (assessed by inulin clearance) increased 55 percent and effective renal plasma flow (assessed by para-amino-hippurate clearance) increased by 32 percent; these increases were sustained through the 96 weeks of therapy. Furthermore, gains in renal function were sustained without adversely affecting 24-hour urinary protein excretion, sodium excretion, or body fluid composition. These results suggest that enalapril, in combination with hydrochlorothiazide, has the pharmacologic capability to favorably modify a primary pathophysiologic characteristic of essential hypertension by decreasing renal vascular and mesangial tone.
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PMID:Hemodynamic and renal function in essential hypertension during treatment with enalapril. 299 41

Enhanced renal vasoconstriction and renal tubular sodium reabsorption mediated by noradrenaline and angiotensin II (Ang II) have been implicated in the pathogenesis of essential hypertension. Since these effects seem to be calcium-dependent, renal haemodynamic and tubular function were studied following acute and long-term treatment with the calcium antagonist felodipine in 10 patients with essential hypertension. After acute felodipine administration mean blood pressure (MBP) decreased (from 111 to 95 mmHg; P less than 0.01), renal blood flow (RBF), estimated from hippurate clearance, increased (from 1030 to 1175 ml/min; P less than 0.01) and glomerular filtration rate (GFR) was unchanged (109 versus 112 ml/min). Fractional excretion (FE) of sodium, potassium, calcium, magnesium, chloride, bicarbonate and urate increased for 12 h. Following long-term felodipine treatment, mean blood pressure was reduced (97 mmHg; P less than 0.01) and RBF and GFR were unchanged (1032 and 114 ml/min, respectively). Fractional excretion of urate and calcium was increased for 24 h (from 5.9 to 6.9%; P less than 0.05 and from 1.1 to 1.3%; P less than 0.05, respectively). Serum urate decreased (from 377 to 347 mumol/l; P less than 0.01) whereas serum calcium was unchanged. Fractional excretion of sodium, potassium and chloride was increased between 3 and 6 h after felodipine. The renal haemodynamic findings after acute felodipine administration are indicative of a direct renal vasodilator action of felodipine which augments the autoregulatory renal vasodilation to produce an overall increase in RBF. Since GFR was unchanged, the increased renal excretion of electrolytes and urate reflects an action at the tubular level. Following long-term felodipine administration autoregulatory adjustment of RBF predominated.
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PMID:Renal effects of acute and long-term treatment with felodipine in essential hypertension. 336 Nov 21

An exercise-mediated renal omicron-iodohippurate transport abnormality was recently identified in patients with hypertension. The disturbance was not observed in normotensive controls. To learn more about this transient functional disturbance of the kidney, we obtained gamma camera hippurate renograms in 45 patients with hypertension. The final diagnoses indicated that 27 patients had essential hypertension, 15 had renal parenchymal or renovascular hypertension, 2 had malignant hypertension, and 1 had hypertension of pregnancy. We documented age, height, weight, global and unilateral renal function, blood pressure status, and antihypertensive medication used at time of scintigraphy. We also noted the serum catecholamine, sodium, and potassium levels. All patients were scintigraphed at rest and during exercise. The scintigraphic examination documented exercise-induced renal dysfunction in 28 (62%) patients (abnormal exercise renogram), while 17 (38%) had renograms not noticeably influenced by the exercise protocol (normal exercise renogram). When the results of scintigraphy were compared with the clinical data, a weak correlation was found between patient overweight and an abnormal response to exercise. There was no significant difference between groups with normal and abnormal exercise renograms with respect to the other parameters assessed. Exercise renography was not useful for differentiating renal and essential hypertension. Renography appears to demonstrate an exercise-mediated, transient, renal perfusion disturbance in certain patients with hypertension. The examination appears to assess a new parameter in hypertensive disease. Thus, the gamma camera renogram should be reevaluated in the patient with hypertension.
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PMID:Clinical evaluation of patients with hypertension and exercise-induced renal dysfunction. 362 82

Intravenous (i.v.) infusion of the selective vasopressin (V2) agonist 1-desamino-8-D-arginine vasopressin (DDAVP, Desmopressin) in humans causes a fall in blood pressure, an increase in heart rate, and a rise in plasma renin and noradrenaline. The present study was designed to demonstrate the vasodilatory properties of DDAVP in the renal circulation and to describe the effect of DDAVP on renin secretion. Seven male subjects (31-63 years) with hypertension, who showed no signs of renal parenchymal disease, received an i.v. infusion of DDAVP (400 ng/kg in 10 minutes). They were studied at the time they were undergoing renal vein renin sampling and renal angiography as part of the diagnostic work-up of their hypertension. 131I-Hippurate clearance was used to measure effective renal plasma flow (ERPF). True renal plasma flow was calculated as ERPF divided by the renal extraction ratio of 131I-hippurate. 125I-Thalamate clearance was used to measure glomerular filtration rate (GFR). Measurements were made before and 15-20 minutes after administration of DDAVP. Angiography was performed in the same session after the last blood samples had been collected. In all patients the renal arteries were normal and the extraction ratios of 131I-hippurate and 125I-thalamate (Ehip, Ethal) were not different for the left and right kidney, and in all seven patients a diagnosis of essential hypertension was made. After DDAVP systolic blood pressure decreased by 14.4 mmHg (2.0-26.8) (mean, 95% confidence interval, p < 0.05). Diastolic blood pressure decreased by 12.1 mmHg (2.9-21.7, p < 0.01). Heart rate increased by 17.5 bpm (11.7-23.2, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of DDAVP on renal hemodynamics and renin secretion in subjects with essential hypertension. 795 85

Spontaneously hypertensive rats (SHR) and their substrains are a useful model for studying essential hypertension which is a complex, polygenic, and multifactorial disorder. Their genetic and metabolic features are of great interest because they may provide insights into the mechanism of blood pressure regulation. We have compared urinary metabolic profiles of young SHR with those of their age-matched normotensive controls, Wistar Kyoto rats, using (1)H NMR-based metabonomics. Principal components analysis was applied to the NMR spectral data after data-reduced and normalized by the total integral or the creatinine integral. Consequently, a clear separation of urine samples between the two strains was observed in the principal components scores plot. The loadings plot from the data normalized by the creatinine integral showed that many metabolites such as citrate, alpha-ketoglutarate, and hippurate contributed to the separation, and the urinary levels of most metabolites used in this study, including these three, were lower in SHR than in Wistar Kyoto rats. These metabolic changes may be concerned with blood pressure regulation in SHR, although a relation to other strain differences cannot be ruled out. The present study suggests the usefulness of a (1)H NMR-based metabonomic approach using SHR in the field of hypertension research.
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PMID:1H NMR-based metabonomic analysis of urine from young spontaneously hypertensive rats. 1816 75


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