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

A sensitive assay method to evaluate the inhibitor of Na+, K+-ATPase in human urine was developed by measuring the inorganic phosphate liberated from ATP in vitro using Na+, K+-ATPase from porcine cerebral cortex. Ouabain inhibited the Na+, K+-ATPase by competing with the potassium ion (an apparent Ki = 2.6 +/- 0.89 X 10(-8) M, n = 8) under the condition of 100 mM NaCl, 4.5 mM MgSO4 and 0.56 mM ATP. The apparent Km value of KCl was 0.4 mM. Factors inhibiting Na+, K+-ATPase were detected in the post-salt fraction on Sephadex G-15 chromatography following the ethanol extraction of lyophilized fresh urine of sodium loaded human subjects (300 meq Na+/day, for 4 days) with essential hypertension. Two active fractions around the 400 daltons following salt were eluted on Sephadex G-15 chromatography. The slower eluted factor competed kinetically with potassium ion, but the inhibitory activity was lost within two days during storage at 4 degrees C. The faster-eluted inhibitor lost its activity within a day. These results indicate that the unstable inhibiting factors of Na+, K+-ATPase exist in human urine and one of these factors inhibits ouabain sensitive Na+, K+-ATPase by binding to the potassium binding site (or very close to it), which exists at the outer surface of the cell membrane of this enzyme.
 ...
PMID:Sensitive assay and kinetic property of urinary inhibitor of Na+, K+-ATPase in sodium-loaded patients with essential hypertension. 299 60

The present study was designed to determine whether magnesium (Mg) deficiency is present in patients with essential hypertension. We measured the retention of an intravenously administered Mg load (0.2 mmol/kg MgSO4 over 4 h), and serum and erythrocyte Mg concentrations in 17 inpatients with essential hypertension and in 15 normotensive controls. There was no significant difference between the two groups in erythrocyte Mg concentration (normotensives vs., hypertensives: 2.0 +/- 0.5 vs. 2.1 +/- 0.4 mmol/l cells), serum Mg concentration (normotensives vs. hypertensive: 2.1 +/- 0.2 vs. 2.1 +/- 0.2 mg/dl), or in urinary Mg excretion (normotensives vs. hypertensives: 65.8 +/- 25.5 vs. 73.7 +/- 26.7 mg/day). However, Mg retention was significantly higher in hypertensives than in normotensives (normotensives vs. hypertensives: 31.8 +/- 12.1 vs. 41.9 +/- 13.3%). These results suggest that a systemic Mg deficiency, which is undectectable by serum or erythrocyte Mg determination, may exist in patients with essential hypertension.
 ...
PMID:Systemic magnesium deficiency disclosed by magnesium loading test in patients with essential hypertension. 758 8

Sodium (Na) restriction and potassium (K) supplementation has been recommended as treatment of essential hypertension but the mechanism by which these may reduce blood pressure (BP) is unknown. We examined if moderately reduced Na intake, combined with a low-Na/high-K salt alternative (Pansalt: NaCl 57%, KCl 28%, MgSO4 12%) as substitute for standard table salt, induced clinically significant BP reduction in hypertensive patients and, if this therapy reduced total peripheral resistance. After a 2-month control period 40 patients aged 21-67 years with mean casual BP 156/103 mmHg were given a salt restricted diet (120 mmol Na/24 h) for 6 months. In addition, they were randomised in a double-blind manner to receive either Pansalt (P-group) or standard NaCl (S-group) as table salt in small amounts. Cardiac output was measured by dye dilution. Daily Na excretion was similarly reduced (20%) in both groups while K excretion was slightly increased in the P-group and reduced in the S-group (difference p < 0.05). No large changes occurred in 24-h ambulatory BP (by Accutracker II) or intraarterial pressure (through a brachial artery catheter) at rest or during exercise while casual BP was reduced (p < 0.05) 13/8 mmHg in the P-group and 8/5 mmHg in the S-group. While cardiac output was slightly reduced at rest and during 50W exercise in the P-group, no significant changes were seen in total peripheral resistance in either group. Thus, moderate reduction in Na intake, with or without addition of K, is not sufficient to induce significant long-term intraarterial or 24-h ambulatory BP changes in essential hypertension. Without BP changes invasively determined central hemodynamics remains remarkably stable over a 6-month period.
 ...
PMID:Unchanged central hemodynamics after six months of moderate sodium restriction with or without potassium supplement in essential hypertension. 773 95