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)

A 52-year-old man had hypertension, persistent hyperkalemia, and hyperchloremic metabolic acidosis; renal and adrenal functions were normal. Four other members of the family have the same findings. The patient's plasma aldosterone (PA) level was within normal range, though plasma renin activity (PRA) was undetectable. The ability to conserve sodium with increased endogenous aldosterone levels, and the inability to increase potassium excretion while exogenous mineralocorticoid (fludrocortisone acetate) was administered, indicated a distal tubular defect in potassium handling. Effective reduction of the hyperkalemia by K+ -Na+ exchange resin also corrected the acidosis and the hyperchloremia, suggesting that hyperkalemia may cause metabolic acidosis.
 ...
PMID:Familial hyperkalemia, hypertension, and hyporeninemia with normal aldosterone levels. A tubular defect in potassium handling. 63 41

A 44-year old woman without history of hypertension in her 4 pregnancies was hospitalized for hemoptysia and found to have hypertension 230/120 to 250/150: she had been taking 2 tablets of Lyndiol (5 mg lynestrenol and .15 mg mestranol) daily for 2 years without medical supervision. Findings included: hypokalemia (2.5 mEq/1), hyperchloremia (105 mEq/1), elevated aldosterone excretion (27 m cg/24 hours), low plasma renin activity (5 ng/1/minute). The initial diagnosis of an aldosterone secreting tumor was discarded and the oral contraceptive incriminated when her blood pressure fell, her lab finding normalized and she lost 3 kg within 6 weeks while on a normal diet. Several weeks after her blood pressure had remained 140/80 to 150/90, she was hospitalized again and given 2 tablets of Lyndiol daily while consuming a diet of 100 mEq sodium per day. The only change was a definite increase in plasma renin substrate from 1300-2300 ng/ml. The authors suggested that the hypertension observed in some pill users is due to hyper-aldo-steronism not resulting from stimulation of the renin-angiotensin system.
 ...
PMID:[A case of arterial hypertension imputable to an estroprogestational contraceptive. Implication of the renin-angiotensin-aldosterone system]. 431 41

A rare syndrome has been described in which mineralocorticoid-resistant hyperkalemia of renal origin occurs in the absence of glomerular insufficiency and renal sodium wasting and in which hyperchloremic acidosis, hypertension, and hyporeninemia coexist. The primary abnormality has been postulated to be a defect of the potassium secretory mechanism of the distal nephron. The present studies were carried out to investigate the mechanism of impaired renal potassium secretion in a patient with this syndrome. When dietary intake of sodium chloride was normal, renal clearance of potassium was subnormal (CK/GFR = 3.6 +/- 0.2%; normal subjects, 9.0 +/- 0.9%, N = 4) despite high normal or supernormal levels of plasma and urinary aldosterone. The fractional clearance of potassium remained subnormal (CK/GFR = 5.1 +/- 0.2%) during superimposed chronic administration of superphysiologic doses of mineralocorticoid hormone. Little increase in renal potassium clearance occurred when the delivery of sodium to distal nephron segments was increased further by the i.v. infusion of sodium chloride, despite experimentally sustained hypermineralocorticoidism. But potassium clearance increased greatly when delivery of sodium to the distal nephron was increased by infusion of nonchloride anions: sulfate (sodium sulfate infusion, low sodium chloride diet; CK/GFR = 63.7 +/- 0.4%) or bicarbonate (sodium bicarbonate plus acetazolamide infusion; CK/GFR = 81.7 +/- 1.7%). These findings indicate that mineralocorticoid-resistant renal hyperkalemia in this patient cannot be attributed to the absence of a renal potassium secretory capability or to diminished delivery of sodium to distal nephron segments; instead it may be dependent on chloride delivery to the distal nephron. We suggest that the primary abnormality in this syndrome increases the reabsorptive avidity of the distal nephron for chloride, which (1) limits the sodium and mineralocorticoid-dependent voltage driving force for potassium and hydrogen ion secretion, resulting in hyperkalemia and acidosis and (2) augments distal sodium chloride reabsorption resulting in hyperchloremia, volume expansion, hyporeninemia, and hypertension.
 ...
PMID:Mineralocorticoid-resistant renal hyperkalemia without salt wasting (type II pseudohypoaldosteronism): role of increased renal chloride reabsorption. 702 72

A 56-year-old white female presented with longstanding hyperkalemia, hyperchloremia, and hypertension. Renal function was normal. Plasma renin levels were low as were serum and urinary aldosterone. Plasma cortisol levels were normal. Fludrocortisone was ineffective in lowering serum potassium. Plasma renin and aldosterone levels responded appropriately to salt restriction and to postural changes. Plasma atrial natriuretic hormone (ANH) and urinary prostaglandins (PG) were normal. Salt loading resulted in suppression of renin and aldosterone levels and stimulation of plasma ANH and urinary PG but failed to increase potassium or chloride excretion. The persistent hyperkalemia, hyperchloremia, and suppressed renin-aldosterone axis were consistent with type II pseudohypoaldosteronism. Hydrochlorothiazide was effective in normalizing serum potassium levels and blood pressure. These studies exclude abnormalities in ANH and PG secretion in this disorder and are compatible with an abnormality in chloride reabsorption.
 ...
PMID:Type II pseudohypoaldosteronism. Report of a case and review of the literature. 793 Mar 91

We describe a case of a 26 year old patient affected by a rare syndrome characterized by hyperkalemia, arterial hypertension and normal glomerular filtration rate (Gordon's syndrome), probably due to a renal tubular defect in the reabsorption of sodium or chloride. The patient, who had hyperkalemia since the age of 4 years, was referred to our Centre because of hypertension not well controlled with antihypertensive treatment. After drug therapy wash-out, we confirmed the existence of hypertension (180/100 mm Hg; ambulatory BP monitoring: 24-h mean BP = 151/91 mm Hg; 7 am-11 pm = 157/95; 11 pm-7 am: 133/82) and blood and urine tests showed hyperkalemia (6.6 mEq/L), hyperchloremia (115 mEq/L), mild metabolic acidosis (pH = 7.35, HCO3 = 19 mEq/L), low levels of plasma renin activity ( < 0.2 ng/ml/h), slight increase of plasma (1.08 nM/L) and daily urine aldosterone (129 nM) and normal serum creatinine (1.1 mg/dl) and glomerular filtration rate (91 ml/min). These data allowed to exclude the presence of renal failure and hyporeninemic hypoaldosteronism, which are the most common diseases with hypertension and hyperkalemia, and suggested the diagnosis of Gordon's syndrome. After 1 month of treatment with chlorthalidone (12.5 mg o.i.d) we observed the normalization of BP (130/80 mm Hg; ambulatory BP monitoring: 24-h BP: 132/76 mm), serum potassium (5,1 mEq/L) and the other blood and urine tests. These results were confirmed 6 months later and at present the patient has good clinical conditions.
 ...
PMID:[Hypertension, hyperpotassemia and normal glomerular filtration (Gordon's syndrome): a case report]. 868 60

Essential hypertension is a common multifactorial trait. The molecular basis of a number of rare diseases that after blood pressure in humans has been established, identifying pathways that may be involved in more common forms of hypertension. Pseudohypoaldosteronism type II (PHAII, also known as familial hyperkalaemia and hypertension or Gordon's syndrome; OMIM #145260), is characterized by hyperkalaemia despite normal renal glomerular filtration, hypertension and correction of physiologic abnormalities by thiazide diuretics. Mild hyperchloremia, metabolic acidosis and suppressed plasma renin activity are variable associated findings. The pathogenesis of PHAII is unknown, although clinical studies indicate an abnormality in renal ion transport. As thiazide diuretics are among the most efficacious agents in the treatment of essential hypertension, understanding the pathogenesis of PHAII may be of relevance to more common forms of hypertension. Analysis of linkage in eight PHAII families showing autosomal dominant transmission demonstrates locus heterogeneity of this trait, with a multilocus lod score of 8.1 for linkage of PHAII to chromosomes 1q31-q42 and 17p11-q21. Interestingly, the chromosome-17 locus overlaps a syntenic interval in rat that contains a blood pressure quantitative trait locus (QTL). Our findings provide a first step toward identification of the molecular basis of PHAII.
 ...
PMID:Multilocus linkage of familial hyperkalaemia and hypertension, pseudohypoaldosteronism type II, to chromosomes 1q31-42 and 17p11-q21. 917 36

A 27-year-old Turkish male presented with fatigue, long lasting hypertension, hyperkalemia, hyperchloremic metabolic acidosis and normal glomerular filtration rate. His brother also showed hyperkalemia with no other features of the disease. Plasma renin levels were low and serum aldosterone levels were inappropriately low-normal to his hyperkalemia. Plasma cortisol levels were normal. Plasma renin aldosterone levels responded appropriately to postural changes, salt restriction and saline infusion. Fludrocortisone was ineffective in his hyperkalemia. The conditions were consistent with Type II pseudohypoaldosteronism (PHA). Furosemide and sodium bicarbonate were effective to control his hyperchloremia, metabolic acidosis and hypertension but partly effective for his hyperkalemia. dDAVP alone did not control the situation and hypertension and metabolic derangement reoccurred. Adding dDAVP to furosemide and sodium bicarbonate successfully controlled hyperkalemia, hyperchloremic acidosis and hypertension. The patient stayed normotensive with normal metabolic and biochemical parameters after 6 months with furosemide and dADVP although sodium bicarbonate had been discontinued after the first month of therapy. dDAVP is a useful adjunct to furosemide and non chloride anions which altogether successfully reverse the metabolic derangement in Type II PHA.
 ...
PMID:Furosemide and dDAVP for the treatment of pseudohypoaldosteronism type II. 949 9

Pseudohypoaldosteronism type II (PHA2) is a rare autosomal dominant form of volume-dependent low-renin hypertension characterized by hyperkalemia and hyperchloremic acidosis but also by a normal glomerular filtration rate. These features, together with the correction of blood pressure and metabolic abnormalities by small doses of thiazide diuretics, suggest a primary renal tubular defect. Two loci have previously been mapped at low resolution to chromosome 1q31-42 (PHA2A) and 17p11-q21 (PHA2B). We have now analyzed a new, large French pedigree, in which 12 affected members over three generations confirmed the autosomal dominant inheritance. Affected subjects had hypertension together with long-term hyperkalemia (range 5.2-6.2 mmol/liter), hyperchloremia (range: 100-109 mmol/liter), normal plasma creatinine (range: 63-129 mmol/liter) and low renin levels. Genetic linkage was excluded for both PHA2A and PHA2B loci (all LOD scores Z<-3.2 at recombination fraction [theta] 0), as well as for the thiazide-sensitive sodium-chloride cotransporter gene. A genome-wide scan using 383 microsatellite markers showed a strong linkage with the chromosome 12p13 region (maximum LOD score Z=6.18, straight theta=0, at D12S99). Haplotype analysis using 10 additional polymorphic markers led to a minimum 13-cM interval flanked by D12S1652 and D12S336, thus defining a new PHA2C locus. Analysis of two obvious candidate genes (SCNN1A and GNb3) located within the interval showed no deleterious mutation. In conclusion, we hereby demonstrate further genetic heterogeneity of this Mendelian form of hypertension and identify a new PHA2C locus, the most compelling and precise linkage interval described to date.
 ...
PMID:A new locus on chromosome 12p13.3 for pseudohypoaldosteronism type II, an autosomal dominant form of hypertension. 1086 38

Mutations in the serine-threonine kinases WNK1 and WNK4 [with no lysine (K) at a key catalytic residue] cause pseudohypoaldosteronism type II (PHAII), a Mendelian disease featuring hypertension, hyperkalemia, hyperchloremia, and metabolic acidosis. Both kinases are expressed in the distal nephron, although the regulators and targets of WNK signaling cascades are unknown. The Cl(-) dependence of PHAII phenotypes, their sensitivity to thiazide diuretics, and the observation that they constitute a "mirror image" of the phenotypes resulting from loss of function mutations in the thiazide-sensitive Na-Cl cotransporter (NCCT) suggest that PHAII may result from increased NCCT activity due to altered WNK signaling. To address this possibility, we measured NCCT-mediated Na(+) influx and membrane expression in the presence of wild-type and mutant WNK4 by heterologous expression in Xenopus oocytes. Wild-type WNK4 inhibits NCCT-mediated Na-influx by reducing membrane expression of the cotransporter ((22)Na-influx reduced 50%, P < 1 x 10(-9), surface expression reduced 75%, P < 1 x 10(-14) in the presence of WNK4). This inhibition depends on WNK4 kinase activity, because missense mutations that abrogate kinase function prevent this effect. PHAII-causing missense mutations, which are remote from the kinase domain, also prevent inhibition of NCCT activity, providing insight into the pathophysiology of the disorder. The specificity of this effect is indicated by the finding that WNK4 and the carboxyl terminus of NCCT coimmunoprecipitate when expressed in HEK 293T cells. Together, these findings demonstrate that WNK4 negatively regulates surface expression of NCCT and implicate loss of this regulation in the molecular pathogenesis of an inherited form of hypertension.
 ...
PMID:Molecular pathogenesis of inherited hypertension with hyperkalemia: the Na-Cl cotransporter is inhibited by wild-type but not mutant WNK4. 1251 52

Familial hyperkalemia and hypertension (FHH; pseudohypoaldosteronism type II) is an autosomal dominant disorder characterized by hyperkalemia, hypertension, and low renin. WNK1 kinase overexpression and WNK4 kinase inactivating missense mutations cause FHH. When expressed in frog oocyte, WNK4 inhibits Na-Cl cotransporter surface expression, and WNK1 relieves this inhibition. We have reported hypercalciuria in subjects with the WNK4 Q565E mutation. In contrast, in subjects with WNK1 overexpression, normocalciuria was found. Here we report a major extension of our previously described kindred that contains 34 subjects, 18 of them affected by the mutation. Hypertension was diagnosed in 13 affected subjects at the age of 31 +/- 12 yr. Five of the affected or obligatory affected subjects had stroke, in four at the age of 50-62 yr. Seven subjects with FHH were diagnosed 27 yr previously. All four subjects who were normotensive at diagnosis became hypertensive during follow-up. The mean time between detection of hyperkalemia and appearance of hypertension was 13 yr. In the extended kindred, compared with the unaffected subjects, affected subjects had hyperkalemia, low transtubular potassium gradient, hyperchloremia, low bicarbonate, higher aldosterone, and marked suppression of renin. Urinary calcium levels in affected and unaffected subjects were 0.85 +/- 0.27 and 0.28 +/- 0.12 mmol/mmol creatinine, respectively (P < 0.0001). Hypercalciuria was accompanied by lower serum calcium levels [9.44 +/- 0.15 vs. 9.81 +/- 0.31 mg/dl (2.36 +/- 0.04 vs. 2.45 +/- 0.08 mmol/liter); P = 0.01], supporting a mechanism of renal calcium leak. The six affected, currently normotensive subjects had the same degree of hyperkalemia, hypercalciuria, and low renin as the affected hypertensive subjects. We conclude that in FHH with WNK4 mutations, with time all affected subjects will apparently develop hypertension. Hypercalciuria accompanies hyperkalemia, and both precede hypertension. Based on the recent findings that WNK4 regulates the renal outer medullary potassium channel as well as epithelial Cl(-)/base exchanger and the Na(+)-K(+)-2Cl(-) cotransporter, we suggest that WNK4 interacts with a calcium channel or transporter.
 ...
PMID:Hypercalciuria in familial hyperkalemia and hypertension accompanies hyperkalemia and precedes hypertension: description of a large family with the Q565E WNK4 mutation. 1529 44


1 2 Next >>