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1.
Georgian Med News ; (278): 34-38, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29905542

RESUMEN

Preterm labor is an urgent medical-social and demographic issue at the present stage. A considerable number of factors affects the course of pregnancy and its outcome, their effect is realized at the level of the central nervous system through numerical metabolic interactions, where monoaminergic systems play an important role. Objective - to study the features of the sympathoadrenal system state by determining the excretion level of DOPHA, dopamine, norepinephrine and epinephrine in women's daily urine with different periods of abortion. 227 pregnant women who were admitted to the Kharkiv perinatal center have been examined, 190 of them had clinical signs of premature delivery in the gestation period of 23-36 weeks. Formation of clinical groups was carried out depending on the pregnancy term in the form of premature and timely delivery. Diagnosis of preterm labor was carried out in the presence of abdominal pain syndrome and structural changes in the cervix. Consequently, pregnancy compensatory and adaptive mechanisms are complex of neurohumoral process, which are realized through monoaminergic systems and a significant factor in its interruption is their destabilization. Reducing of sympathoadrenal system activity and reserve capacity in pregnant women may be a pathogenetic factor in the development of preterm labor. Therefore determination of the imbalance initial manifestations in the catecholamines exchange may possibly prevent the loss of pregnancy in the early stages.


Asunto(s)
Aborto Espontáneo/fisiopatología , Sistema Hipotálamo-Hipofisario/fisiopatología , Trabajo de Parto Prematuro/fisiopatología , Sistema Hipófiso-Suprarrenal/fisiopatología , Nacimiento Prematuro/fisiopatología , Aborto Espontáneo/orina , Adulto , Estudios de Casos y Controles , Dihidroxifenilalanina/orina , Dopamina/orina , Epinefrina/orina , Femenino , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Recién Nacido , Norepinefrina/orina , Trabajo de Parto Prematuro/orina , Sistema Hipófiso-Suprarrenal/metabolismo , Embarazo , Tercer Trimestre del Embarazo , Nacimiento Prematuro/orina
2.
J Clin Invest ; 47(10): 2359-73, 1968 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-5676529

RESUMEN

Intravenous administration of tritium-labeled 3,4-dihydroxyphenylalanine (dopa) to human subjects resulted in the labeling of endogenous catecholamines and vanillylmandelic acid (VMA). Determination of the changes in specific activity of these compounds with time in fractional collections of urine and in cardiac biopsies from patients undergoing corrective cardiac surgery permitted estimation of apparent turnover rates. The average half-time of the exponential decline in specific activity of labeled urinary norepinephrine was about 8 hr and that of VMA was 11-16 hr in five normal subjects. No significant differences from normal were observed in eight patients with essential hypertension. The average half-life of norepinephrine was only 5 hr in cardiac patients undergoing surgery, and the levels and rate of decline of cardiac norepinephrine specific activity correlated well with the exponential phase of the urinary disappearance curve. There were significant effects of treatment with alpha-methyltyrosine, reserpine, and pargyline hydrochloride on the labeling and apparent turnover rates of norepinephrine and VMA; the effects noted were consistent with known actions of these three drugs. It is suggested that the technique used is a suitable means of assessing "over-all" catecholamine metabolism in man, particulary if combined with quantitative assay of urinary catecholamine metabolites.


Asunto(s)
Catecolaminas/metabolismo , Hipertensión/metabolismo , Metiltirosinas/farmacología , Pargilina/farmacología , Reserpina/farmacología , Simpaticolíticos/farmacología , Adolescente , Adulto , Presión Sanguínea/efectos de los fármacos , Catecolaminas/análisis , Cromatografía , Dihidroxifenilalanina/metabolismo , Dihidroxifenilalanina/orina , Dopamina/orina , Epinefrina/orina , Circulación Extracorporea , Femenino , Humanos , Masculino , Ácidos Mandélicos/análisis , Ácidos Mandélicos/orina , Persona de Mediana Edad , Miocardio/análisis , Norepinefrina/análisis , Norepinefrina/orina , Cardiopatía Reumática/metabolismo , Cardiopatía Reumática/cirugía , Espectrofotometría , Tritio
3.
Cancer Res ; 36(9 pt.1): 3317-23, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-975093

RESUMEN

By using ion-exchange column chromatography with effluent monitoring using the stable, free radical alpha,alpha-diphenyl-beta-picryhydrazyl as a colorimetric reagent, we have demonstrated the occurrence of elevated levels of five peaks in the urine of patients with metastatic disease. The tentative assignment of two of the peaks as 3,4-dihydroxyphenylalanine and as 3-methoxy-4-hydroxyphenylalanine has been made. Three remain unknown. The correlation of these peaks with the clinical status of melanoma patients shows that, while the individual excretion pattern of these compounds may be variable, the sustained occurrence of one or more of them in a patient's urine is evidence of recurrent or continuing disease. The excretion levels appear to be proportional to the tumor burden. The results with a group of 39 melanoma patientshaving Stage II or Stage III disease indicate that this chromatography technique provides earlier evidenc eof liver metastases than doses the liver scan, may detect occult metastases generally, and has detected tumor in clinically enlarged lymph nodes. This method, in its present form, does not detect small pulmonary lesions earlier than chest X-ray or tomography do or brain metastases earlier than do brain scan or computerized axial tomography. The technique is clinically useful for the diagnosis of melanoma patients and in their follow-up while under treatment.


Asunto(s)
Dihidroxifenilalanina/orina , Melanoma/diagnóstico , Metildopa/orina , Cromatografía por Intercambio Iónico , Cisteinildopa/orina , Femenino , Humanos , Masculino , Melanoma/orina , Metástasis de la Neoplasia
4.
J Invest Dermatol ; 70(4): 197-9, 1978 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-641370

RESUMEN

A simple screening test for estimation of some phenolic and indolic compounds in urine is described. The method is rapid, simple and able to detect all the indolic and phenolic compounds observed, including o-dihydroxy compounds. The method is based on the color reaction with reagent solution composed of sodium tungstate, trichloroacetic acid, hydrochloric acid and sodium nitrite. After alkalinization by sodium hydroxide the optical density is measured at 405 and 490 nm. The latter is specific for o-dihydroxy compounds. This test seems to be useful for estimation of phenolic and indolic compounds in urine of patients with increased production of compounds of this nature, particularly in some tumors.


Asunto(s)
Indoles/orina , Melanoma/orina , Fenoles/orina , Neoplasias Cutáneas/orina , Ácido 3,4-Dihidroxifenilacético/orina , Dihidroxifenilalanina/orina , Humanos , Ácido Hidroxiindolacético/orina , Melanoma/diagnóstico , Neoplasias Cutáneas/diagnóstico
5.
Hypertension ; 18(5): 614-21, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1937664

RESUMEN

Dopamine in urine is derived substantially from renal uptake and decarboxylation of 3,4-dihydroxyphenylalanine (dopa), and increases in excretion of dopa normally parallel increases in excretion of dopamine during salt loading. Since patients with salt-sensitive hypertension may have decreased urinary excretion of dopamine during dietary salt loading, the present study was designed to evaluate the response of dopa to salt loading. Sixteen inpatients with normal-renin essential hypertension ate a constant metabolic diet containing 9 mmol/day sodium for 7 days, followed by the same diet but containing 249 mmol/day sodium for 7 days. Salt sensitivity was defined as an increase in mean arterial pressure of 8 mm Hg between the diets; on this basis, nine patients were salt-sensitive and seven, salt-resistant. The rate of urinary dopa excretion was significantly higher in the salt-sensitive patients throughout the study (mean rates 132 +/- 13 nmol/day in the salt-sensitive group and 78 +/- 9 nmol/day in the salt-resistant group for the 14 days of observation, p less than 0.01). When dietary sodium intake was increased to 249 mmol/day, urinary dopa excretion increased significantly more in salt-sensitive patients than salt-resistant patients. At the end of the high salt diet, dopamine excretion was significantly attenuated in the salt-sensitive patients, despite higher rates of dopa excretion. Thus, the urinary ratio of dopamine to dopa was decreased in salt-sensitive patients, regardless of salt intake.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Dihidroxifenilalanina/orina , Dopamina/orina , Hipertensión/orina , Cloruro de Sodio/farmacología , Adolescente , Adulto , Anciano , Presión Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Sodio/orina
6.
Hypertension ; 17(6 Pt 2): 997-1002, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1904403

RESUMEN

To explore whether an altered metabolic pathway of dihydroxyphenylalanine (DOPA) may be related to some previously observed dopamine abnormalities in borderline hypertension, we measured basal and DOPA-induced (500 mg orally) changes in blood pressure and pulse rate as well as in three hourly plasma and urine samples. We found that borderline hypertensive patients compared with controls 1) showed a higher baseline urinary excretion of methoxytyramine, a marker of exocytotic dopamine release, with a greater DOPA-induced decrease of systolic blood pressure without reflex tachycardia; 2) had in response to DOPA a blunted plasma DOPA and free dopamine increase but an accentuated plasma dopamine sulfate and urinary DOPAC excretion; and 3) eliminated comparable quantities of dopamine in urine despite a lower rise in the glomerular DOPA load. Furthermore, although DOPA elicited natriuresis in both groups, its effect was greater in borderline hypertensive patients, who lacked the urinary sodium correlation with urinary dopamine excretion seen in control subjects. These data are compatible with increased basal exocytotic dopamine release and accelerated neuronal and renal (extraneuronal) dopamine generation from administered DOPA in borderline hypertension. The DOPA-induced hypernatriuresis exceeding augmented dopamine in borderline hypertensive patients, contrasting with the urinary sodium and dopamine correlation in control subjects, suggests that DOPA induced an additional natriuresis in borderline hypertensive patients by a decrease in renal sympathetic tone because of its central inhibition of sympathetic outflow, which also may account for the absence of reflex tachycardia.


Asunto(s)
Dopamina/metabolismo , Hipertensión/metabolismo , Adulto , Presión Sanguínea/efectos de los fármacos , Dihidroxifenilalanina/sangre , Dihidroxifenilalanina/farmacología , Dihidroxifenilalanina/orina , Dopamina/sangre , Dopamina/orina , Femenino , Humanos , Riñón/metabolismo , Masculino , Persona de Mediana Edad , Natriuresis/efectos de los fármacos , Pulso Arterial/efectos de los fármacos , Tirosina/sangre , Tirosina/metabolismo , Tirosina/orina
7.
Hypertension ; 23(1 Suppl): I240-5, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8282367

RESUMEN

To evaluate the additive effect of moderate chronic renal failure to the abnormal dopamine generation and action observed in stable hypertension, we investigated 22 age-matched patients with a comparable degree of hypertension with and without chronic renal failure. Both groups were compared with each other and with an age-matched control group after a single oral dose of dihydroxyphenylalanine (DOPA) while cardiorenal responses and DOPA, dopamine, and their metabolites were measured. The hypertensive patients with chronic renal failure shared with their hypertensive counterparts without chronic renal failure an impaired DOPA decarboxylation to dopamine. However, patients with chronic renal failure had decreased hemodynamic and normal natriuretic responses compared with the hypernatriuresis of hypertensive patients with normal renal function; patients with chronic renal failure had elevated basal plasma concentrations of DOPA and dopamine sulfates as well as increased plasma and urinary DOPA sulfate but blunted urinary dopamine sulfate increases after DOPA administration; they presented augmented plasma atrial natriuretic factor concentrations. Thus, hypertensive patients with moderate chronic renal failure exhibit a decreased hemodynamic responsiveness to DOPA administration-induced dopamine elevation but with the natriuretic effect of dopamine maintained (possibly because of its permissive interaction with increased atrial natriuretic factor levels). Hypertensive patients with chronic renal failure have a heightened DOPA and dopamine sulfoconjugating propensity. Dopamine sulfate attenuates the biologic action of free dopamine. This may contribute (possibly via glomerular hypertension and hyperfiltration due to decreased postglomerular vasodilation) to progressive hypertensive renal damage, particularly in groups predisposed to dopamine deficiency, such as diabetics, blacks, and the elderly.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Dihidroxifenilalanina/sangre , Hipertensión/fisiopatología , Fallo Renal Crónico/fisiopatología , Levodopa/farmacología , Ácido 3,4-Dihidroxifenilacético/orina , Factor Natriurético Atrial/sangre , Creatinina/metabolismo , Diástole/efectos de los fármacos , Dihidroxifenilalanina/orina , Dopamina/sangre , Dopamina/orina , Femenino , Ácido Homovanílico/orina , Humanos , Hipertensión/etiología , Hipertensión/metabolismo , Fallo Renal Crónico/sangre , Fallo Renal Crónico/orina , Masculino , Persona de Mediana Edad , Valores de Referencia , Sodio/orina
8.
J Hypertens ; 9(3): 259-63, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1851789

RESUMEN

We measured daily urinary excretion rates of dopamine and dopa during dietary salt loading and natriuretic responses to exogenous dopamine in Dahl salt-sensitive (DS), Dahl salt-resistant (DR) and Sprague-Dawley rats. Excretion rates of dopa increased approximately sixfold during salt loading in all rat strains. Maximal urinary dopa responses were attained within 1 day of salt loading. Daily excretion rates of dopamine also increased about five- to sixfold in DS and DR rats and about twofold in Sprague-Dawley rats, with maximal dopamine responses attained by day 5. Dopamine infusion (3 micrograms/kg per min) increased urinary sodium excretion by 406 +/- 132 % (mean +/- s.e.m.) in Sprague-Dawley rats but only 267 +/- 131% and 147 +/- 80% in DS and DR rats (P less than 0.05 for Sprague-Dawley versus Dahl rats). The results demonstrate that salt loading markedly and rapidly increases dopa excretion in rats. Considering values for dopamine excretion in other rat strains, the results suggest that Dahl rats have increased formation of dopamine for a given amount of dopa delivery to the kidney and that this abnormality is unrelated to salt-sensitive hypertension in DS rats. The results also provide in vivo support for the view that the responsiveness of renal dopamine receptors mediating natriuresis is related to production of endogenous dopamine in the kidney.


Asunto(s)
Dihidroxifenilalanina/orina , Dopamina/orina , Hipertensión/orina , Sodio en la Dieta/farmacología , Animales , Dopamina/farmacología , Hipertensión/etiología , Riñón/química , Riñón/fisiopatología , Masculino , Natriuresis/fisiología , Ratas , Ratas Endogámicas , Receptores Dopaminérgicos/fisiología , Factores de Tiempo
9.
Br J Pharmacol ; 117(6): 1193-8, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8882615

RESUMEN

1. The present study has examined the effect of (+)-WAY 100135, a selective antagonist of 5-HT1A receptors, and ketanserin, an antagonist of 5-HT2 receptors, on the urinary excretion of Na+, K+, dopamine, 5-hydroxytryptamine (5-HT) and their metabolites in rats treated with the selective type A monoamine oxidase (MAO-A) inhibitor, Ro 41-1049 (15 mg kg-1 day-1) in conditions of normal sodium (NS) and high sodium (HS; 1.0% NaCl in drinking water) intake. 2. Male Wistar rats were placed in metabolic cages and were given tap water (NS diet) in the first 4 days of the study and then challenged to a HS diet for another 7 days. Ro 41-1049 was given in drinking water only in the last 3 days of the HS diet, whereas (+)-WAY 100135 (5 and 10 mg kg-1 day-1, s.c.) or ketanserin (2 mg kg-1 day-1, s.c.) were administered in the last 4 days of the HS intake period. 3. Daily urinary excretion (in nmol kg-1 day-1) of dopamine (82 +/- 2), 3,4-dihydroxyphenylacetic acid (DOPAC; 198 +/- 9), homovanillic acid (HVA; 915 +/- 47), 5-HT (586 +/- 37) and 5-hydroxyindoleacetic acid (5-HIAA; 1035 +/- 64) in the HS intake period was similar or higher than that in NS diet (dopamine = 68 +/- 2, DOPAC = 197 +/- 4, HVA = 923 +/- 42, 5-HT = 539 +/- 132, 5-HIAA = 1286 +/- 95). The administration of Ro 41-1049 on 3 consecutive days reduced the urinary excretion of dopamine, DOPAC and HVA, respectively, by 35-51% (P < 0.05), 73-85% (P < 0.05) and 59-66% (P < 0.05); the urinary excretion of 5-HT increased 2 fold (P < 0.01) and the levels of 5-HIAA were reduced by 39-77% (P < 0.05). 4. During HS intake (7 days), daily urinary excretion of Na+ increased 5.5 fold (from 6.7 +/- 0.2 to 36.5 +/- 0.9 mmol kg-1 day-1), without changes in the urinary excretion of K+ (from 11.2 +/- 0.2 to 11.9 +/- 0.5 mmol kg-1 day-1) and urinary osmolality (from 1083.8 +/- 26.7 to 1117.7 +/- 24.1 mOsm kg-1 H2O). MAO-A inhibition during HS intake was found to produce a 47-68% decrease in Na+ excretion (from 39.1 +/- 0.7 to 15.1 +/- 2.5 mmol kg-1 day-1, n = 4; P < 0.02) and urine volume (from 160.4 +/- 3.3 to 43.8 +/- 9.0 ml kg-1 day-1, n = 4; P < 0.02) without changes in K+ (from 11.1 +/- 0.5 to 9.2 +/- 0.6 mmol kg-1 day-1, n = 4) and creatinine (from 29.1 +/- 2.3 to 28.4 +/- 2.1 mg kg-1 day-1) excretion; urine osmolality increased 2 fold (from 936.3 +/- 40.3 to 2210.7 +/- 157.4 mOsm kg-1 H2O, n = 4; P < 0.02). Administration of (+)-WAY 100135 (5 and 10 mg kg-1 day-1), but not of ketanserin (2 mg kg-1 day-1), was found to inhibit the antinatriuretic effect induced by Ro 41-1049 during HS intake. 5. It is suggested that MAO-A inhibition during HS intake leads to an increased availability of 5-HT in renal tissues, the effect of which is a decrease in the urinary excretion of Na+, involving the activation of tubular 5-HT1A receptors.


Asunto(s)
Dihidroxifenilalanina/orina , Ketanserina/farmacología , Túbulos Renales Proximales/efectos de los fármacos , Piperazinas/farmacología , Receptores de Serotonina/fisiología , Antagonistas de la Serotonina/farmacología , Serotonina/orina , Sodio/administración & dosificación , Animales , Hemodinámica/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Masculino , Natriuresis/efectos de los fármacos , Potasio/orina , Ratas , Ratas Wistar , Factores de Tiempo
10.
Environ Health Perspect ; 30: 91-5, 1979 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-446464

RESUMEN

The effect of exposure to different amounts of polychlorocamphene (toxaphene) on the level of cathecholamines (noradrenalin and adrenalin), their precursors (DOPA and dophamine), and a metabolite (vanillylmandelic acid) in tissues (adrenals, brain, heart) and daily urine in white male rats has been studied. It was established that the single administration of 120 mg/kg toxaphene (half the LD50) as well as 2.4 mg/kg (1/100 of LD50) for 1 and 3 months produced a disturbance of catecholamine metabolism. The absolute level of ratio of separate components of the sympathicoadrenalic system is unequally changed in tissues, the breakdown of catecholamines is increased, and the specificity of their excretion is destroyed.


Asunto(s)
Catecolaminas/metabolismo , Insecticidas/toxicidad , Sistema Nervioso Simpático/efectos de los fármacos , Toxafeno/toxicidad , Glándulas Suprarrenales/metabolismo , Animales , Encéfalo/metabolismo , Dihidroxifenilalanina/metabolismo , Dihidroxifenilalanina/orina , Dopamina/metabolismo , Dopamina/orina , Epinefrina/metabolismo , Epinefrina/orina , Masculino , Miocardio/metabolismo , Norepinefrina/metabolismo , Norepinefrina/orina , Ratas , Ácido Vanilmandélico/metabolismo , Ácido Vanilmandélico/orina
11.
Am J Hypertens ; 6(1): 33-40, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8427659

RESUMEN

The previously observed defective dopamine (DA) generation from 3,4-dihydroxyphenylalanine (DOPA) can also be seen in patients treated for many years by hydralazine. This may be due to a hydralazine-induced depletion of pyridoxine, an essential coenzyme of the aromatic L-amino acid decarboxylase (LAAD). Eleven hydralazine-treated stable essential hypertensive (EH) patients, initially found to have a defect in the DOPA decarboxylation to DA, tested by a single DOPA administration (500 mg, orally), were retested by the same test 4 days after pyridoxine pretreatment (100 mg/day) for data on blood pressure (BP), pulse rate, and renal and plasma catecholamines and their metabolites, as well as plasma atrial natriuretic factor (ANF), cyclic GMP (cGMP), plasma renin activity (PRA), and plasma aldosterone (PA). Initially, hydralazine-treated stable EH patients manifested, following DOPA administration, lower DOPA decarboxylation to DA than control subjects. Pyridoxine pretreatment accelerated DA generation from exogenous DOPA and attenuated the DOPA-induced increases in plasma and urinary DOPA and its metabolite 3-O-methyl-DOPA, but accentuated the increase in free DA and its main metabolites, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), while BP, ANF, cGMP, PRA, and PA remained unaffected. The DOPA-induced increments of urinary DA were, in contrast to plasma DA changes, blunted by pyridoxine pretreatment. The attenuation of the sodium excretion by pyridoxine pretreatment exceeded that of the DA excretion, suggesting that pyridoxine suppressed a natriuretic factor, other than ANF, or activated a sodium-retaining factor, other than renin or aldosterone.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Dihidroxifenilalanina/metabolismo , Dopamina/metabolismo , Hidralazina/uso terapéutico , Hipertensión/tratamiento farmacológico , Piridoxina/uso terapéutico , Adulto , Sistema Cardiovascular/efectos de los fármacos , Descarboxilación/efectos de los fármacos , Dihidroxifenilalanina/sangre , Dihidroxifenilalanina/orina , Diuresis/efectos de los fármacos , Dopamina/sangre , Dopamina/orina , Femenino , Hormonas/sangre , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Riñón/efectos de los fármacos , Levodopa , Masculino , Persona de Mediana Edad , Sodio/metabolismo
12.
Metabolism ; 38(4): 322-9, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2498609

RESUMEN

Increasing evidence relates serum insulin level and blood pressure in obese individuals. Although the connection between these two factors is not established, a common presumption is that the sympathetic nervous system is somehow involved, in part, because laboratory studies demonstrate insulin stimulation of sympathetic and cardiovascular activity. Because the obese may exhibit altered responsiveness to insulin action, the current investigation compared cardiovascular and neurohumoral responses to euglycemic insulin infusion (200 mU/m2/min) in obese and lean men. At baseline, obese men displayed higher glucose and insulin levels, faster pulse rates, and elevated mean arterial pressures (MAP) than lean controls; plasma norepinephrine (NE) and 3,4-dihydroxyphenylalanine (DOPA) concentrations, however, did not differ. During insulin infusion, pulse rate increased equally in obese and lean subjects (from 69 to 78 min-1 in obese and from 56 to 66 min-1 in lean subjects), while MAP remained unchanged in both groups. Elevations in plasma NE (+85 pg/mL in obese and +109 in lean pg/mL) and reductions in plasma DOPA (-233 pg/mL in obese and -376 pg/mL in lean) did not differ between groups. Sodium excretory rate decreased during insulin infusion in lean subjects by 2.2 mEq/h but increased in obese by 5.3 mEq/h (difference in response between groups, P = .024). Thus, in these obese men, cardiovascular and sympathetic responses to insulin persist despite evidence of moderate insulin resistance; increased sympathetic activity, as a cause for the resting tachycardia and borderline hypertension at baseline, seems unlikely.


Asunto(s)
Dihidroxifenilalanina/sangre , Insulina/farmacología , Norepinefrina/sangre , Obesidad/sangre , Adulto , Glucemia/análisis , Presión Sanguínea , Dihidroxifenilalanina/orina , Dopamina/orina , Electrólitos/orina , Humanos , Insulina/sangre , Masculino , Norepinefrina/orina , Obesidad/fisiopatología , Obesidad/orina , Potasio/sangre , Pulso Arterial
13.
Eur J Pharmacol ; 370(3): 271-8, 1999 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-10334502

RESUMEN

This study assess the effects of glucocorticoids on dopamine excretion and evaluates the participation of renal dopamine in the effects of glucocorticoids on renal function and Na+ excretion. Dexamethasone (i.m.; 0.5 mg/kg) was administered to male Wistar rats on day 2 or on days 2 and 5. Daily urinary excretions of Na+, dihydroxyphenylalanine (DOPA), dopamine and dihydroxyphenylacetic acid were determined from day 1 to day 7. Renal function was evaluated 8 h after dexamethasone administration in a separate group. The first dose of dexamethasone increased about 100% diuresis and natriuresis, increased urinary DOPA and renal plasma flow, and did not affect urinary dopamine or the other parameters evaluated. These effects were not affected by previous administration of haloperidol. The second dexamethasone dose increased about 200% diuresis and natriuresis, increased urinary dopamine, DOPA, dihydroxyphenylacetic acid, Uosm x V and both glomerular filtration rate and renal plasma flow. Carbidopa administered before the second dexamethasone dose blunted both the diuretic and the natriuretic response whereas haloperidol abolished or blunted all the effects of the second dexamethasone dose. These results show that modifications in renal dopamine production produced by corticoids may contribute to the effects of these hormones on Na+ balance and diuresis and suggest that regardless the factor that promotes an increase in renal perfusion and glomerular filtration rate during long term administration of glucocorticoids, a dopaminergic mechanism is actively involved in the maintenance of these hemodynamic changes.


Asunto(s)
Dexametasona/farmacología , Dopamina/biosíntesis , Glucocorticoides/farmacología , Riñón/efectos de los fármacos , Natriuresis/efectos de los fármacos , Ácido 3,4-Dihidroxifenilacético/orina , Animales , Cardiotónicos/farmacología , Dihidroxifenilalanina/orina , Diuresis/efectos de los fármacos , Dopamina/orina , Dopaminérgicos/farmacología , Interacciones Farmacológicas , Tasa de Filtración Glomerular/efectos de los fármacos , Haloperidol/farmacología , Riñón/metabolismo , Masculino , Ratas , Ratas Wistar
14.
J Hum Hypertens ; 9(4): 263-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7595909

RESUMEN

We examined the reproducibility of dietary salt-sensitivity testing by studying the effects on blood pressure (BP) of low sodium intake (20 mmol/day) and high sodium intake (220 mmol/day) in 10 men with borderline hypertension on two separate occasions. A difference in mean arterial pressure of 8 mm Hg between the high salt and the low salt regimen was arbitrarily chosen to define salt sensitivity. In addition, the reproducibility of changes in renal haemodynamics and in humoral factors, such as plasma renin activity, plasma aldosterone, atrial natriuretic peptide and urinary dopa and dopamine excretion, on the alteration in sodium intake were studied. As far as changes in BP are concerned, there was perfect agreement between the two tests, because in the second investigation, all subjects were classified in the same category as before. The salt-induced changes in plasma atrial natriuretic peptide and in renal excretion of dopa (dihydroxyphenylalanine) and dopamine were repeatedly and consistently different between the salt-sensitive and the salt-resistant group. The study revealed no support for a role of renal haemodynamics or the renin-angiotensin-aldosterone system in the pathophysiology of salt-induced elevations of BP in salt-sensitive subjects.


Asunto(s)
Dieta Hiposódica , Hipertensión/fisiopatología , Adulto , Presión Sanguínea , Peso Corporal , Dihidroxifenilalanina/orina , Dopamina/orina , Electrólitos/sangre , Frecuencia Cardíaca , Hemodinámica , Hormonas/sangre , Humanos , Masculino , Persona de Mediana Edad , Circulación Renal , Reproducibilidad de los Resultados
15.
Arch Dermatol Res ; 275(2): 76-9, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6409012

RESUMEN

Cysteinyldopas and Dopa in the urine and tissues of Japanese melanoma patients were investigated quantitatively by means of high-performance liquid chromatography. Cysteinyldopa isomers were detected in the urine of eumelanic Japanese patients. The amount (X +/- SD%) of each isomer of cysteinyldopa in the urine was 80.26 +/- 4.66% in 5-S-cysteinyldopa, 9.39 +/- 1.64% in 2-S-cysteinyldopa, 7.07 +/- 3.33% in 2, 5-S, S-dicysteinyldopa, and 3.28 +/- 1.43% in 6-S-cysteinyldopa. The amount of cysteinyldopa in melanoma tissues was 26-314 times more than that of Dopa. The amount (X +/- SD%) of cysteinyldopa in the tissues was 80.34 +/- 1.75% in 5-S-cysteinyldopa, 11.06 +/- 1.91% in 2-S-cysteinyldopa, 6.27 +/- 1.43% in 2, 5-S, S-dicysteinyldopa, and 2.34 +/- 0.61% in 6-S-cysteinyldopa. The fact that the percentages of each isomer of cysteinyldopa in the urine and in the tissues were approximately constant suggests that the cysteinyldopas secreted from melanoma cells were excreted into the urine without being metabolized.


Asunto(s)
Cisteinildopa/orina , Dihidroxifenilalanina/análogos & derivados , Dihidroxifenilalanina/orina , Melanoma/orina , Neoplasias Cutáneas/orina , Cisteinildopa/análisis , Dihidroxifenilalanina/análisis , Humanos , Isomerismo , Japón , Metástasis Linfática , Melanoma/análisis , Neoplasias Cutáneas/análisis
16.
Adv Neurol ; 14: 319-27, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-941777

RESUMEN

Determinations of various catecholamines and their metabolites have been performed on 24-hr urine collecions obtained from a patient with torsion dystonia and compared to values obtained in a control population. This study was initiated following significant symptomatic worsening by the patient with supplemental ascorbic acid at a dosage of 2 g/day. Compared to base-line values, there resulted no significant alteration in urinary excretion of DOPA, dopamine, norepinephrine, epinephrine, or VMA for either the patient or a group of controls, receiving 1 g/day vitamin C. MHPG is the glycol metabolite of norepinephrine, and is produced both in central and systemic tissues, whereas VMA is not synthesized in brain. The MHPG excretion for the patient increased 150% with supplemental ascorbate, whereas the control individuals demonstrated a mean increase of 19.6%. It is possible that the symptomatic worsening by the patient and the increased excretion of MHPG in response to supplemental ascorbic acid are causally related. Ascorbic acid affects catecholamine biosynthesis at two metabolic loci; it is the necessary cofactor for dopamine-beta-hydroxylase and, by maintaining biopterin in reduced form, facilitates tyrosine hydroxylase holoenzyme activity. Thus, the vitamin may have effected increased central synthesis or turnover of norepinephrine, or both, with resultant clinical worsening.


Asunto(s)
Ácido Ascórbico/uso terapéutico , Distonía Muscular Deformante/tratamiento farmacológico , Adulto , Ácido Ascórbico/administración & dosificación , Dihidroxifenilalanina/orina , Dopamina/orina , Distonía Muscular Deformante/orina , Epinefrina/orina , Femenino , Humanos , Metoxihidroxifenilglicol/orina , Norepinefrina/orina , Ácido Vanilmandélico/orina
17.
Artículo en Inglés | MEDLINE | ID: mdl-9231300

RESUMEN

Urinary catecholamine excretion was assessed in 15 boys with attention-deficit/hyperactivity disorder (ADHD) and 16 normal controls during a defined physical and mental task. Dihydroxyphenylalanine, dopamine, norepinephrine (NE), epinephrine (EPI), 3,4-dihydroxyphenylacetic acid, and 3,4-dihydroxyphenylglycol (DOPEG) concentrations were assayed by high-pressure liquid chromatography with electrochemical detection. The urinary concentration of DOPEG, an NE metabolite that has not been previously measured in ADHD, was significantly lower in the ADHD subjects than in the normal controls. There was also a trend for lower urinary EPI levels in the hyperactive boys. Stepwise multiple regression analyses demonstrated that DOPEG and EPI each contributed significantly to the variance in the behavioral symptoms within the full sample. The results are consistent with previous reports of abnormal metabolism of norepinephrine and epinephrine in ADHD. These neurochemical findings may be due to differences between ADHD and normal boys in neuronal (central or peripheral) or nonneuronal (e.g., adrenal, renal) activity. The results are also consistent with prior findings in normal children of an inverse relationship between EPI excretion and inattentive, restless behaviors. Together, these findings suggest caution in ascribing metabolite changes to ADHD or to ADHD-like behaviors that may be seen in normal children.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/orina , Catecolaminas/orina , Conducta Infantil , Ácido 3,4-Dihidroxifenilacético/orina , Niño , Dihidroxifenilalanina/orina , Dopamina/orina , Epinefrina/orina , Humanos , Masculino , Metoxihidroxifenilglicol/análogos & derivados , Metoxihidroxifenilglicol/orina , Norepinefrina/orina , Reflejo de Sobresalto
18.
J Pharm Pharmacol ; 42(4): 242-6, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1974290

RESUMEN

gamma-L-Glutamyl-L-dopa (gludopa) is believed to be a dopamine prodrug specific for the kidney. Its pharmacokinetics have been studied in the rat given 50 mg kg-1 intravenously (i.v.) and 60 mg kg-1 intraperitoneally (i.p.). By the i.v. route, elimination followed apparent first order kinetics and was biphasic with a t 1/2 alpha of 7 min and terminal half-life of 67 min. After i.p. administration absorption was rapid (t 1/2 ab 6 min), elimination was monophasic with a terminal half-life almost identical following i.v. dosing (65 min), and bioavailability was 40%. In tissues (liver and kidney) gludopa was biotransformed to four intact catecholic products (L-dopa, dopamine, DOPAC and gamma-L-glutamyl-dopamine) which appeared quickly (peaks at 15 min) and which were almost completely cleared by 4 h. Dopamine was the major kidney metabolite accounting for 69% of total catechol content with an AUC 31 times greater than in liver where it accounted for only 34% of total catechols. In rat urine eight major metabolites (5.7% of the dose) and at least 12 minor metabolites were detected of all of which 85% was dopamine. A higher percentage of the dose was excreted as intact catechols in man (15.7%) but fewer metabolites were detected (L-dopa, dopamine, DOPAC). It is confirmed that gludopa is kidney specific in rat but that the pharmacological effects of dopamine are likely to be short lived due to rapid clearance. Gludopa appears to be less dopamine specific in man.


Asunto(s)
Dihidroxifenilalanina/análogos & derivados , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Disponibilidad Biológica , Dihidroxifenilalanina/metabolismo , Dihidroxifenilalanina/farmacocinética , Dihidroxifenilalanina/orina , Dopamina/metabolismo , Femenino , Humanos , Riñón/metabolismo , Levodopa/metabolismo , Hígado/metabolismo , Persona de Mediana Edad , Ratas , Ratas Endogámicas , Distribución Tisular
19.
Tumori ; 67(4): 325-32, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6797117

RESUMEN

A qualitative gas chromatographic analysis of trimethylsilylated ethyl acetate extracts of melanotic urine revealed 5 indolic compounds, which have been identified as substituted 5,6-dihydroxyindoles. Ethyl acetate extracts of melanotic urines at pH 2.0 contained isomeric 5-hydroxy-6-methoxy and 6-hydroxy-5-methoxy-indolyl-2-carboxylic acids which were not separable under the conditions used. A careful hydrolysis of melanotic urine with a Helix pomatia preparation followed by extraction at pH 6.5 in a nitrogen atmosphere released 3 additional indolic compounds from their conjugated form. Using gas chromatographic-mass spectrometric analysis they were identified as 5-hydroxy-6-methoxy, 6-hydroxy-5-methoxyindole and 5,6-dihydroxyindole.


Asunto(s)
Dihidroxifenilalanina/orina , Indoles/orina , Melanoma/orina , Neoplasias Cutáneas/orina , Cromatografía de Gases , Humanos , Melaninas/biosíntesis
20.
Artículo en Ruso | MEDLINE | ID: mdl-654723

RESUMEN

The study concerns some results of the catecholamine metabolism in torsion dystonia. The author found certain changes of the excretion of catecholamines that were different in patients with various clinical manifestations of the disease. The most expressed changes were observed in patients with prevalent local regidity of the muscles in the clinical picture. They were seen in significant descrease of the excretion of all catecholamines and DOPA; the most expressed was a decrease of dopamine and adrenalin discharge. Along with this in prevalent torsion spastic hyperkinesis in the clinical picture there was a tendency towards an increase of dopamine excretion (in the absence of DOPA and noradrenalin changes), and a decreased adrenalin excretion. A conclusion is drawn concerning heterogeneity of torsion dystonia that deals with a clinical polymorphism of the disease. The author discusses the pathogenetical significance of the found biochemical disturbances.


Asunto(s)
Catecolaminas/orina , Dihidroxifenilalanina/orina , Distonía Muscular Deformante/orina , Adolescente , Adulto , Anciano , Niño , Dopamina/orina , Epinefrina/orina , Femenino , Humanos , Judíos , Masculino , Persona de Mediana Edad , Norepinefrina/orina , Síndrome
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