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1.
Diabetes Obes Metab ; 18(5): 483-90, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26799632

RESUMEN

AIMS: To assess the safety and pharmacokinetic and pharmacodynamic characteristics of BI 135585, a selective 11ß-hydroxysteroid dehydrogenase-1 (11ß-HSD1) inhibitor, after single- and repeated-dose administration. METHODS: The single-dose study included open-label administration of 200 mg BI 135585 in healthy volunteers, while in the multiple-dose study, we carried out randomized, double-blind administration of 5-200 mg BI 135585 or placebo once daily over 14 days in patients with type 2 diabetes (T2DM). Assessments included 11ß-HSD1 inhibition in the liver (urinary tetrahydrocortisol (THF)/tetrahydrocotisone (THE) ratio) and in subcutaneous adipose tissue (AT) ex vivo and determination of hypothalamus-pituitary-adrenal (HPA) axis hormone levels. RESULTS: No major safety issues occurred with BI 135585 administration. The HPA axis was mildly activated with slightly increased, but still normal adrenocorticotropic hormone levels, increased total urinary corticoid excretion but unchanged plasma cortisol levels. After multiple doses of 5-200 mg BI 135585, exposure (area under the curve) increased dose-proportionally and half-life was 55-65 h. The urinary THF/THE ratio decreased, indicating liver 11ß-HSD1 inhibition. Median 11ß-HSD1 enzyme inhibition in the AT reached 90% after a single dose of BI 135585, but was low (31% or lower) after 14 days of continuous treatment. CONCLUSIONS: BI 135585 was safe and well tolerated over 14 days and can be dosed once daily. Future studies are required to clarify the therapeutic potential of BI 135585 in view of its effects on 11ß-HSD1 inhibition in AT after single and multiple doses. Enzyme inhibition in the AT was not adequately predicted by the urinary THF/THE ratio.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , Inhibidores Enzimáticos/efectos adversos , Hipoglucemiantes/efectos adversos , Hígado/efectos de los fármacos , Oxazinas/efectos adversos , Piridonas/efectos adversos , Grasa Subcutánea/efectos de los fármacos , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Hormona Adrenocorticotrópica/sangre , Adulto , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/enzimología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Femenino , Glucocorticoides/orina , Hemoglobina Glucada/análisis , Semivida , Humanos , Hidrocortisona/sangre , Hiperglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/uso terapéutico , Hígado/enzimología , Masculino , Persona de Mediana Edad , Mineralocorticoides/orina , Oxazinas/administración & dosificación , Oxazinas/farmacocinética , Oxazinas/uso terapéutico , Piridonas/administración & dosificación , Piridonas/farmacocinética , Piridonas/uso terapéutico , Grasa Subcutánea/enzimología
2.
Nephrol Dial Transplant ; 28(6): 1526-32, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23413088

RESUMEN

BACKGROUND: Blockade of the mineralocorticoid receptor (MR) in patients with chronic kidney disease (CKD) improves surrogate cardiovascular outcomes, such as left ventricular mass. Animal models of renal disease support a pathological role of mineralocorticoids, in the context of a high sodium intake. We aimed to assess the regulation of mineralocorticoid biosynthesis in patients with CKD. METHODS: Seventy patients with CKD stages 3/4 and 30 patients with essential hypertension (EH) were recruited. Patients underwent detailed clinical phenotyping, drug history and biochemical assessment. Patients completed a 24-h urine collection for measurement of urinary tetrahydroaldosterone (THALDO) and tetrahydrocorticosterone (THDOC) excretion rates (measured using gas chromatography-mass spectrometry) and urinary electrolytes. The factors which correlated significantly with THALDO and THDOC excretion were entered into linear regression models. RESULTS: Patients with EH and CKD were well matched with no significant differences in gender, age or weight. The mean estimated glomerular filtration rate (eGFR) in CKD patients was 38.6/min/1.73 m(2). The mean urinary excretion rates of THALDO, THDOC and 24-h urinary sodium (24-h USod) were not significantly different between CKD and EH patients. The level of renal function did not correlate with THALDO or THDOC excretion. In patients with CKD, 24-h USodium (r = 0.614, P < 0.001) and 24-h UPotassium (r = 0.538, P < 0.001) were positively correlated with THALDO excretion. On multivariate linear regression analysis, 24-h USod was the strongest independent predictor (P = 0.004) of THALDO and THDOC excretion in CKD. In patients with EH, no relationship was seen between mineralocorticoid excretion and 24-h urinary sodium excretion. CONCLUSIONS: In patients with CKD, 24-h urinary sodium excretion is the strongest positive predictor of urinary mineralocorticoid excretion. The nature of this relationship is unexpected, novel, not seen in patients with EH and may explain the association seen between high urinary sodium excretion, mineralocorticoids and poor outcomes in patients with CKD.


Asunto(s)
Aldosterona/análogos & derivados , Corticosterona/análogos & derivados , Hipertensión/orina , Mineralocorticoides/orina , Insuficiencia Renal Crónica/orina , Sodio/orina , Aldosterona/orina , Estudios de Cohortes , Corticosterona/orina , Estudios Transversales , Hipertensión Esencial , Femenino , Cromatografía de Gases y Espectrometría de Masas , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
3.
J Steroid Biochem Mol Biol ; 198: 105553, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31778802

RESUMEN

21-hydroxylase deficiency, the most common enzyme defect associated with congenital adrenal hyperplasia (CAH) is characterized by an impairment of both aldosterone and cortisol biosynthesis. Close clinical and biological monitoring of Hydrocortisone (HC) and 9α-Fludrocortisone (FDR) replacement therapies is required to achieve an optimal treatment. As frequent and repeated reassessments of plasma steroids, 17-hydroxyprogesterone (17-OHP), androstenedione (Δ4-A) and testosterone (TESTO) is needed in childhood, urine steroid profiling could represent an interesting non-invasive alternative. We developed and validated a LC-MS/MS method for the measurement of 23-urinary mineralocorticoids, glucocorticoids and adrenal androgens. The usefulness of steroid profiling was investigated on single 08h00 am-collected spot urine for discriminating between 61 CAH patients and their age- and sex-matched controls. CAH patients were split into two groups according to their 08h00 am-plasma concentrations of 17-OHP: below (controlled patients, n = 26) and above 20 ng/mL (uncontrolled patients, n = 35). The lower limit of quantification and the wide analytical range allows to assay both free and total concentrations of the main urinary adreno-corticoids and their tetra-hydrometabolites. Extraction recoveries higher than 75% and intra-assay precision below 20% were found for most steroids. Urinary steroids upstream of the 21-hydroxylase defect were higher in uncontrolled CAH patients. Among CAH patients, plasma and urinary 17-OHP were closely correlated. As compared to controls, steroids downstream of the enzyme defect collapsed in CAH patients. This fall was more pronounced in controlled than in uncontrolled patients. Androgens (Δ4-A, TESTO and the sum etiocholanolone + androsterone) accumulated in uncontrolled CAH patients. A strong relationship was observed between plasma and urinary levels of androstenedione. Daily doses and urinary excretion of both FDR and HC were similar in both CAH groups. Urinary FDR was inversely related to the sodium-to-potassium ratio in urine. A partial least squares discriminant analysis model allowed to classify the patient's classes unaffected, controlled and un-controlled CAH patients based on urinary steroidomic profiles. Our LC-MS/MS method successfully established steroid profiling in urine and represents a useful and non-invasive tool for discriminating CAH patients according to treatment efficiency.


Asunto(s)
Hiperplasia Suprarrenal Congénita/orina , Andrógenos/orina , Glucocorticoides/orina , Mineralocorticoides/orina , Adolescente , Niño , Preescolar , Cromatografía Liquida/métodos , Femenino , Humanos , Masculino , Espectrometría de Masas en Tándem/métodos
4.
J Clin Endocrinol Metab ; 103(2): 748-758, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29077874

RESUMEN

Context: Urinary cadmium (Cd) excretion is associated with cancer and cardiovascular morbidity. A potential mechanism could be disturbance of steroidogenesis in gonads and adrenal glands. Objective: We tested whether urinary excretion of Cd is correlated with that of cortico- and sex steroid metabolites in the general adult population. Setting: The Swiss Kidney Project on Genes in Hypertension is a multicentric, family-based population study. Measures: Urinary excretions of steroid hormone metabolites and Cd were measured with separate day and night collections. Associations were analyzed by mixed linear models. Results: Urinary Cd and testosterone excretions in men were significantly correlated (respective day and night ß values [standard error (SE)], 1.378 [0.242], P < 0.0005; and 1.440 [0.333], P < 0.0005), but not in women [0.333(0.257), P = 0.2; and 0.674 (0.361), P = 0.06]. Urinary Cd and cortisol excretions were positively associated in both sexes [day: ß = 0.475 (SE, 0.157), P = 0.0025, and 0.877 (SE, 0.194), P < 0.0005, respectively; night: ß = 0.875 (SE, 0.253), P < 0.0005 and 1.183 (SE, 0.277), P = 0.00002, respectively]. Cd excretion was correlated with mineralocorticoid metabolites excretion, except tetrahydroaldosterone, in both sexes (P < 0.01). There was an independent effect of Cd on sex hormone and corticosteroid synthesis and an interdependent effect on gluco- and mineralcorticoid production. Conclusion: Our findings provide evidence for a global stimulating effect on steroid synthesis already at low-dose Cd exposure. These findings might explain the association of Cd with diseases such as steroid-sensitive cancers or metabolic disorders.


Asunto(s)
Corticoesteroides/metabolismo , Cadmio/orina , Hormonas Esteroides Gonadales/metabolismo , Hipertensión/metabolismo , Adulto , Anciano , Aldosterona/análogos & derivados , Aldosterona/orina , Estudios de Cohortes , Familia , Femenino , Hormonas Esteroides Gonadales/orina , Humanos , Hipertensión/orina , Riñón/metabolismo , Masculino , Persona de Mediana Edad , Mineralocorticoides/orina , Testosterona/orina
5.
Clin Cancer Res ; 3(3): 389-94, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9815696

RESUMEN

We describe a patient with a metastasized adrenocortical cancer who exhibited excessive production of both glucocorticoids and mineralocorticoids combined with suppressed androgen production. Unusual steroid metabolites found in the patient's urine have not been described previously in association with this tumor type. Investigation of the multidrug resistance phenotype in single-cell suspensions of the tumor revealed low expression of multidrug resistance protein but high expression of P-glycoprotein (Pgp) and lung resistance-related protein. Functional Pgp in these tumor cells was shown by the modulatory effect of PSC833 on daunorubicin accumulation. Mitotane, at a concentration achieved in this patient's plasma, completely reversed the Pgp-related resistance both in the Pgp-overexpressing KB8-5 cell line and in the patient's tumor cells. On the basis of these in vitro results, the patient was treated with a combination of multidrug resistance drugs (doxorubicin, vincristine, and etoposide) plus mitotane as a Pgp modulator. This treatment was ineffective, however. A chemosensitivity assay demonstrated that the tumor cells were highly resistant to the drugs used. The adrenocortical cancer cells expressed mutant p53, and no evidence for induction of apoptosis by these drugs was found.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/tratamiento farmacológico , Neoplasias de la Corteza Suprarrenal/fisiopatología , Antineoplásicos/toxicidad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/tratamiento farmacológico , Carcinoma/fisiopatología , Resistencia a Múltiples Medicamentos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/genética , Adulto , Andrógenos/orina , Apoptosis , Carcinoma/diagnóstico , Carcinoma/genética , Daunorrubicina/farmacocinética , Daunorrubicina/toxicidad , Doxorrubicina/administración & dosificación , Ensayos de Selección de Medicamentos Antitumorales , Etopósido/administración & dosificación , Genes p53 , Glucocorticoides/orina , Humanos , Masculino , Mineralocorticoides/orina , Mitotano/administración & dosificación , Proteínas de Neoplasias/genética , Células Tumorales Cultivadas , Partículas Ribonucleoproteicas en Bóveda/genética , Vincristina/administración & dosificación
6.
J Clin Endocrinol Metab ; 74(5): 1195-7, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1569167

RESUMEN

19-Noraldosterone, which was recently shown to be synthesized and produced in the human adrenal gland, possesses potent mineralocorticoid activity. 18,19-Dihydroxycorticosterone [18,19-(OH)2B], a possible precursor of 19-noraldosterone, has also been identified in human urine. To elucidate the regulatory mechanism for these newly described steroids, we studied the effect of sodium restriction on the urinary excretion of 19-noraldosterone and 18,19-(OH)2B in six normal subjects. 18,19-(OH)2B and 19-noraldosterone were measured by specific RIAs after purification of the urine extract by high performance liquid chromatography. The 24-h urinary excretion of 19-noraldosterone and 18,19-(OH)2B during the control period were 107 +/- 40 (+/- SE) pmol/day and 5.6 +/- 0.8 nmol/day, respectively. After sodium restriction, the values increased approximately 2-fold (P less than 0.05), to 259 +/- 76 pmol/day and 15.6 +/- 4.5 nmol/day, respectively. Virtually identical responses were seen for aldosterone (from 21 +/- 6.0 to 38 +/- 10 nmol/day), 18-hydroxycorticosterone (from 9.9 +/- 1.1 to 21 +/- 2.8 nmol/day), and 18-hydroxycortisol (from 377 +/- 93 to 554 +/- 129 nmol/day). These observations suggest that 19-noraldosterone and 18,19-(OH)2B are partly under the control of the renin-angiotensin system in normal subjects.


Asunto(s)
18-Hidroxicorticosterona/análogos & derivados , Aldosterona/análogos & derivados , Dieta Hiposódica , Mineralocorticoides/orina , 18-Hidroxicorticosterona/orina , Adulto , Aldosterona/sangre , Aldosterona/orina , Humanos , Masculino , Persona de Mediana Edad , Renina/sangre
7.
Hypertension ; 5(3): 385-9, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6341221

RESUMEN

A number of mineralocorticoids have been proposed as etiologic factors in low-renin hypertension. In this study, urinary free 19-nor-deoxycorticosterone (UF 19-nor-DOC) was compared to other mineralocorticoids--aldosterone, deoxycorticosterone (DOC), and 18-OH-DOC, in 11 low-renin hypertensive patients on a controlled diet in a metabolic unit. Results demonstrated that both UF 19-nor-DOC and tetrahydro-DOC (TH-DOC) excretion were elevated (2086 +/- 926, nl = 339-579 ng/day, and 18 +/- 7, nl = 5-15 mcg/day, respectively), and positively correlated (r = 0.95). Neither 18-OH-DOC nor aldosterone secretion rates were elevated, and neither of these hormones correlated with UF 19-nor-DOC, with exception of the supine plasma aldosterone (SPA) (r = 0.86). In conclusion, both UF 19-nor-DOC and TH-DOC were increased and positively correlated in the present series of hypertensives. This association is possibly indicative of a precursor-product relationship between DOC and 19-nor-DOC. 19-Nor-DOC, furthermore, correlated with supine plasma aldosterone (SPA), which could, in part, reflect their shared adrenocorticotropic hormone (ACTH) dependence.


Asunto(s)
Desoxicorticosterona/análogos & derivados , Hipertensión/orina , Mineralocorticoides/orina , Renina/sangre , 18-Hidroxidesoxicorticosterona/sangre , 18-Hidroxidesoxicorticosterona/orina , Adulto , Aldosterona/sangre , Aldosterona/orina , Desoxicorticosterona/sangre , Desoxicorticosterona/orina , Furosemida/farmacología , Humanos , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Postura
8.
J Clin Endocrinol Metab ; 50(2): 401-4, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6243671

RESUMEN

An infant with severe neonatal hyponatremia and hyperkalemia is described. Although marked elevations of urinary 17-hydroxycorticosteroids suggested an 18-dehydrogenase aldosterone biosynthetic defect, the infant proved to have mineralocorticoid unresponsiveness, or pseudohypoaldosteronism. Dietary sodium supplementation and ion exchange resin administration resulted in normalization of serum electrolytes and urinary 17-hydroxycorticosteroids. ACTH infusion produced natriuresis, suggesting the need for additional sodium supplementation during the stress of illness, with a resultant increase in ACTH secretion. Determinations of the relative amounts of urinary 18-hydroxy and aldosterone metabolites appear necessary for early definitive diagnosis of the disorder.


Asunto(s)
17-Hidroxicorticoesteroides/orina , Hiperpotasemia/metabolismo , Hiponatremia/metabolismo , Enfermedades del Recién Nacido/metabolismo , Mineralocorticoides/orina , Hormona Adrenocorticotrópica , Aldosterona/orina , Femenino , Humanos , Hiperpotasemia/terapia , Hiponatremia/terapia , Recién Nacido , Enfermedades del Recién Nacido/terapia , Potasio/sangre , Potasio/orina , Sodio/sangre , Sodio/orina
9.
J Clin Endocrinol Metab ; 60(4): 631-8, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2982904

RESUMEN

Studies in three families (A, B, and C) revealed five patients with congenital adrenal hyperplasia (CAH) due to partial and combined 21- and 11 beta-hydroxylase deficiency. One patient (A-11 1), a 23-yr-old severely virilized chromosomal female, was reared as a male, and two females (B-11 2 and C-1) complained only of hirsutism, acne, and menstrual abnormalities. Patients A-11 2 and B-11 8 (17 1/2 and 10 yr old) were asymptomatic and detected by finding an HLA genotype identical to that of their respectively affected brother and sister. Three patients (A-11 1, A-11 2, and C-1) had moderate hypertension. In spite of the wide range of clinical manifestations, all individuals had elevated androgen levels, while cortisol secretion was severely impaired only in A-11 2. 21-Hydroxylase deficiency was diagnosed on the basis of markedly increased plasma and urinary levels of 17-hydroxyprogesterone (17-OHP) and 21-deoxycortisol and their respective urinary metabolites pregnanetriol and pregnanetriolone. PRA was elevated in three patients, while urinary aldosterone was normal or increased. 11 beta-Hydroxylase deficiency was diagnosed on the basis of increased 11-deoxycortisol and deoxycorticosterone in plasma and tetrahydro-11-deoxycortisol and deoxycorticosterone in urine, particularly after ACTH administration. In contrast to classical 11 beta-hydroxylase deficiency CAH, urinary 18-hydroxycorticosterone and 18-hydroxy-11-deoxycorticosterone were normal or elevated. The nature and mechanism of a combined enzymatic defect are unknown. The coincidental presence in a single individual of the mutant genes for both 21- and 11 beta-hydroxylase deficiency CAH is very unlikely to occur. Two alternative hypotheses may explain our findings. One is the existence of a genetically inherited abnormal (or aberrant) 11 beta-hydroxylase, whose affinity for its normal substrate is changed for an abnormal one (17-OHP). As a result, 11 beta-hydroxylation of 11-deoxycortisol is deficient while 17-OHP 11 beta-hydroxylation is markedly enhanced. Thus, both 11-deoxycortisol and 21-deoxycortisol as well as their urinary metabolites accumulate. The ability for 18-hydroxylation, however, remains normal. In this case, 21-hydroxylase is not deficient, yet 21-deoxycortisol cannot be further hydroxylated to cortisol, since this steroid is not a suitable substrate for the enzyme. Such a disorder may represent a new allelic variant of 11 beta-hydroxylase deficiency CAH, which, similar to 21-hydroxylase deficiency, is completely linked to the HLA complex.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Hiperplasia Suprarrenal Congénita , Hiperplasia Suprarrenal Congénita/enzimología , Esteroide Hidroxilasas/deficiencia , Hiperplasia Suprarrenal Congénita/genética , Hiperplasia Suprarrenal Congénita/metabolismo , Hormona Adrenocorticotrópica , Adulto , Andrógenos/sangre , Andrógenos/orina , Dexametasona , Femenino , Genotipo , Glucocorticoides/sangre , Glucocorticoides/orina , Antígenos HLA/genética , Humanos , Masculino , Mineralocorticoides/sangre , Mineralocorticoides/orina
10.
J Clin Endocrinol Metab ; 70(4): 1162-6, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2156889

RESUMEN

The family of cytochrome P450 enzymes that mediates steroid hydroxylations are distinct but structurally related proteins. Inhibitors of these steroidogenic steps generally exhibit only relative and dose-related specificity. We evaluated an imidazole, cytochrome P450-related inhibitor, CGS 16949A, in postmenopausal patients with metastatic breast cancer. While a relatively specific aromatase inhibitor at daily dosages of 1-2 mg, CGS 16949A significantly blunted cortisol responses to ACTH at a dose of 16 mg daily. To further evaluate other inhibitory effects of this drug, we determined blood levels of aldosterone (ALDO) and 18-hydroxycorticosterone and their respective urinary metabolites, tetrahydroaldosterone and tetrahydro-18-hydroxy-11-dehydrocorticosterone in 16 postmenopausal women receiving CGS 16949A. At a dose of 16 mg/day, CGS 16949A produced significant (P less than 0.001) suppression of both basal and ACTH-stimulated ALDO production. This was accompanied by a significant rise in the blood 18-hydroxycorticosterone/ALDO ratio (11.4 +/- 0.19; normal, less than 2; P less than 0.001), consistent with a corticosterone methyloxidase type II inhibition. A similar significant elevation (7.5 +/- 1.2; normal, less than 5; P less than 0.001) in the urinary tetrahydro-18-hydroxy-11-dehydrocorticosterone/tetrahydroaldosterone ratio was also observed. These results suggest that CGS 16949A is a potent inhibitor of the corticosterone methyloxidase type II enzyme at a dose of 16 mg daily. At doses of 1-2 mg daily, CGS 16949A blocks aromatase without altering basal aldosterone production and, thus, exhibits dose-related specificity.


Asunto(s)
Corteza Suprarrenal/efectos de los fármacos , Aldosterona/biosíntesis , Inhibidores de la Aromatasa , Citocromo P-450 CYP11B2 , Imidazoles/farmacología , Mineralocorticoides/biosíntesis , Nitrilos/farmacología , 18-Hidroxicorticosterona/análisis , Corteza Suprarrenal/metabolismo , Hormona Adrenocorticotrópica , Anciano , Aldosterona/análogos & derivados , Aldosterona/análisis , Sitios de Unión/efectos de los fármacos , Neoplasias de la Mama/análisis , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/secundario , Fenómenos Químicos , Química , Inhibidores Enzimáticos del Citocromo P-450 , Electrólitos/sangre , Electrólitos/orina , Fadrozol , Femenino , Humanos , Hidrocortisona/análisis , Técnicas In Vitro , Mineralocorticoides/sangre , Mineralocorticoides/orina , Oxigenasas de Función Mixta/antagonistas & inhibidores
11.
J Hypertens ; 16(8): 1187-91, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9794723

RESUMEN

BACKGROUND: Patients with Cushing's syndrome exhibit a bimodal distribution of maximal rates of the erythrocyte amiloride-sensitive Na+/H+ exchange (NHE). Enhanced erythrocyte NHE has recently been found in patients with primary aldosteronism. OBJECTIVE: To test the hypothesis that occult hypermineralocorticoidism in a subset of patients with Cushing's syndrome is responsible for the greater than normal NHE. METHODS: NHE was measured as maximal initial rate (Vmax) of amiloride-inhibited efflux of H+ into an alkaline Na+-containing medium, for 47 patients with hypercortisolism (20 with pituitary adenomas, 18 with adrenal adenomas, and nine with ectopic production of adrenocorticotropin). Clinical appearance, blood pressure levels, plasma aldosterone and deoxycorticosterone levels, serum electrolytes, and urine (tetrahydrocortisol plus 5-alpha-tetrahydrocortisol) : tetrahydrocortisone ratios were assessed for all patients. Twenty patients (10 with greater than normal NHE and 10 with low-to-normal NHE) were randomly selected from 47 patients with hypercortisolism, and treated with 200 mg/day spironolactone for 7 days. NHE in these patients was assessed before starting the treatment and 2 days after its cessation. RESULTS: Greater than normal NHE (Vmax) was associated with peripheral edema, high diastolic blood pressure, hypokalemia, and high urine (tetrahydrocortisol plus 5-alpha-tetrahydrocortisol) : tetrahydrocortisone ratios. The enhanced NHE was rapidly normalized by treatment with spironolactone. CONCLUSION: Erythrocyte NHE in patients with hypercortisolism and functional hypermineralocorticoidism is greater than normal due to incomplete peripheral conversion of cortisol (which binds to mineralocorticoid receptors) into metabolically inactive cortisone.


Asunto(s)
Síndrome de Cushing/sangre , Mineralocorticoides/sangre , Intercambiadores de Sodio-Hidrógeno/sangre , Adulto , Cortisona/metabolismo , Síndrome de Cushing/fisiopatología , Eritrocitos/metabolismo , Femenino , Humanos , Hidrocortisona/metabolismo , Transporte Iónico , Cinética , Masculino , Persona de Mediana Edad , Mineralocorticoides/orina
12.
Thromb Res ; 66(5): 467-73, 1992 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-1326134

RESUMEN

One neglected side effect of heparin therapy is the inhibition of adrenal aldosterone production leading to occasionally life-threatening hyperkalaemia. This is only reported with (therapeutic) high doses (greater than or equal to 20.000 IU). The complex interplay of mineralocorticoid metabolites was studied in 29 subjects with unfractionated (UFH) and low molecular weight heparin (LMWH). Both heparins altered mineralocorticoid metabolism in a dose dependent manner. Whereas no effect was observed with UFH 2 x 5000 IU sc/day or LMWH 2500 a FXa U sc/day, higher doses significantly suppressed aldosterone and 18-hydroxycorticosterone production in plasma and urine. Three out of seven patients receiving UFH 3 x 7500 IU sc/day developed hyperkalaemia. This study shows the threshold dosage of UFH leading to suppression of mineralocorticoid metabolism in man and provides information that LMWH as well as UFH can suppress mineralocorticoid production. With respect to therapeutic implications it is important that LMWH at 2500 a FXa U sc/d had no effect on mineralocorticoid metabolism in contrast to UFH at a dosage currently used for prevention of thromboembolism (3 x 5000 IU sc/d).


Asunto(s)
Heparina de Bajo-Peso-Molecular/farmacología , Heparina/farmacología , Hiperpotasemia/inducido químicamente , Mineralocorticoides/biosíntesis , Adulto , Aldosterona/biosíntesis , Aldosterona/sangre , Aldosterona/orina , Depresión Química , Relación Dosis-Respuesta a Droga , Femenino , Heparina/administración & dosificación , Heparina/efectos adversos , Heparina de Bajo-Peso-Molecular/administración & dosificación , Heparina de Bajo-Peso-Molecular/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Mineralocorticoides/orina
13.
Steroids ; 67(7): 605-10, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11996933

RESUMEN

Pregnancy-induced hypertension (PIH) is a frequent cause of maternal and neonatal morbidity and mortality. 19-Noraldosterone, which was shown to be synthesized in the human adrenal gland, exhibits potent mineralocorticoid and hypertensive activity. To examine the role of mineralocorticoids in the pathophysiology of PIH, we studied urinary 19-noraldosterone, tetrahydroaldosterone, free cortisol, and cortisone concentrations and mineralocorticoid receptor levels in peripheral blood mononuclear leukocytes, from 17 women with PIH and 16 normal pregnant women as controls. Sequence analysis of the mineralocorticoid receptor gene in PIH patients was also done. The 24-h urinary excretion of 19-noraldosterone was significantly lower in PIH (120 +/- 38 pmol/day) than in controls (358 +/- 55 pmol/day) (P < 0.05). Urinary tetrahydroaldosterone was also decreased in PIH compared with controls. Ratios of urinary free cortisol to cortisone (a measure of 11beta-hydroxysteroid dehydrogenase 2 activity) did not differ significantly between groups. Mineralocorticoid receptor density was significantly (P < 0.05) decreased in the PIH group (133 +/- 15 binding sites/cell) compared with controls (255 +/- 21 binding sites/cell). No mutations were found in the coding region of the mineralocorticoid receptor gene in PIH. These results suggest that circulating aldosterone, 19-noraldosterone, and renal 11beta-hydroxysteroid dehydrogenase2 do not contribute to the pathogenesis of PIH. Regulatory factors that cause the down-regulation of the mineralocorticoid receptor in PIH should be clarified.


Asunto(s)
Aldosterona/análogos & derivados , Aldosterona/sangre , Aldosterona/orina , Preeclampsia/sangre , Preeclampsia/orina , Adolescente , Adulto , Femenino , Humanos , Mineralocorticoides/sangre , Mineralocorticoides/orina , Preeclampsia/diagnóstico , Embarazo , Receptores de Mineralocorticoides/análisis , Receptores de Mineralocorticoides/genética
14.
Kardiologiia ; 16(11): 78-83, 1976 Nov.
Artículo en Ruso | MEDLINE | ID: mdl-189116

RESUMEN

The functional state of the cortical and medullar layers of the adrenal glands was studied in 127 patients with primary arterial hypotension (109 females and 18 males, aged 17 to 48 years). As shown by daily urine excretion, hypotonic patients had a decreased basal activity of the glucocorticoid and androgenic function of the adrenal cortex in comparison with those in normal individuals. The potential of the adrenal cortex was preserved in these patients within sufficient limits. The adrenocorticotrophic function of the anterior lobe of the pituitary gland was found to decrease. Against the background of a reduction of the total excretion of all fractions a relative delay was noted in the process of glucocorticoids transformation into their precursors, as well as a relative predominance of glucocorticoids over mineralcorticoids, the content of desoxycorticosterone being reduced especially low. The content of adrenalin, noradrenaline and dophamine was below the normal level, the decrease being statistically significant. At the same time the excretion of DOPA was normal, on the average, the whole group of patients. The changes in the daily urine excretion of catecholamines and DOPA, as well as in their ratio indicate that the activity of both links of the sympathodrenal system is reduced in primary arterial hypotension.


Asunto(s)
Corteza Suprarrenal/fisiopatología , Glándulas Suprarrenales/fisiopatología , Médula Suprarrenal/fisiopatología , Hipotensión/fisiopatología , 17-Hidroxicorticoesteroides/orina , 17-Cetosteroides/orina , Adolescente , Hormona Adrenocorticotrópica , Adulto , Catecolaminas/orina , Dihidroxifenilalanina/orina , Femenino , Glucocorticoides/orina , Humanos , Hipotensión/orina , Masculino , Persona de Mediana Edad , Mineralocorticoides/orina
15.
Hypertens Res ; 33(8): 850-6, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20520614

RESUMEN

It is suggested to use the aldosterone-to-renin ratio (ARR) as a first test in the screening for primary aldosteronism (PA). However, many groups rather rely on the determination of urinary tetrahydroaldosterone secretion; others calculate a ratio of urinary aldosterone to plasma renin activity. The aim of the present study was to evaluate the usefulness of different parameters of aldosterone excess in the case finding of PA. The study included 28 patients with PA and 33 subjects with essential hypertension. Clinical data, which included the hormonal parameters, serum aldosterone, plasma renin concentration, urinary free aldosterone and metabolites and serum and urinary electrolyte levels were analyzed. These indices of aldosterone excess, the ARR, serum sodium to urinary sodium to (serum potassium)(2) to urinary potassium (SUSPPUP) ratio and combinations of these parameters were compared between the groups. Receiver-operating curve analysis revealed that the ARR multiplied by the SUSPPUP ratio (ARR x SUSPPUP) is the most reliable screening test, with a sensitivity of 92.3% and a specificity of 93.9% (cutoff point 199.2 (mmol l(-1))(-1)). The combination of ARR x SUSPPUP ratio with urinary free aldosterone divided by the plasma renin concentration rendered a specificity of 100%. Less useful was the correction of urinary free aldosterone and its metabolites for sodium excretion. Although the ARR and urinary free aldosterone divided by renin are good tests in the screening for PA, the combination of ARR with SUSPPUP ratio is a better indicator of an aldosterone excess and aldosterone action in patients with ongoing antihypertensive medication. Antihypertensive drugs only marginally interfere with the SUSPPUP ratio, but they may influence the ARR, whereby the effects in PA patients seem to be negligible.


Asunto(s)
Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/metabolismo , Hipertensión/diagnóstico , Mineralocorticoides/sangre , Mineralocorticoides/orina , Adulto , Anciano , Aldosterona/sangre , Aldosterona/orina , Biomarcadores/sangre , Biomarcadores/orina , Presión Sanguínea/fisiología , Femenino , Humanos , Hiperaldosteronismo/complicaciones , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Potasio/sangre , Potasio/orina , Valor Predictivo de las Pruebas , Renina/sangre , Sensibilidad y Especificidad , Sodio/sangre , Sodio/orina
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