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

For the quantitative determination of dihydralazine (1) a derivative with acetylacetone in biological material was formed at pH = 4.9, extracted with n-hexane, and measured gaschromatographically with N-P-FID. Acid labile 1 was hydrolyzed with HCl (1 mol/l) for 24 h. The detection limit was 25 nmol/l plasma. Kinetic studies were performed in 16 patients with essential hypertension under steady-state conditions after the oral application of 50 mg 1. The acetylator phenotype was determined with sulfamethazine. Complete dihydralazine plasma level-time courses were found in only 5 cases. The concentrations were below the detection limit in 4 patients for the whole period. Only single values could be registered in the remaining patients. Maximal plasma levels of the free (58-314 nmol/l) and acid labile 1 (147-367 nmol/l) were reached 20-40 min after the application. The elimination half life was 23-47 min for the free 1, 55-92 min for the acid labile 1. Less than 0.5% of the applied drug were excreted into the 24 h urine in its free form, about 0.4% as acid labile derivatives. No correlation could be found between the acetylator phenotype of the patients and the kinetic behaviour of the drug. Preliminary studies concerning the biliary excretion of 1 after i. m. application in two patients with T-drain showed an accumulation of the free compound with bile/plasma ratios up to 7.4.
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PMID:[Quantitative determination and kinetics of dihydralazine in hypertension patients]. 409 28

A simplified radioimmunoassay system for aldosterone secretion rate was developed by using radioiodine-labelled aldosterone and highly specific antiserum to aldosterone. An antibody was produced in rabbits by injecting aldosterone-oxime coupled with bovine gamma-globulin once a month. Aldosterone-oxime was labelled with 125I by using the chloramine T method described by Hunter and Greenwood. 3 ml of a twenty-four-hour urine specimen was used for the radioimmunoassay. Following CH2Cl2 extraction, pH 1 hydrolysis was carried out for twenty-four hours. Separation of the aldosterone extract was achieved by paper chromatography (hexane:benzene:methanol:water = 1:9:5:2.5). The minimum measurable concentration was under 1pg, and adequate intraassay and interassay precision were obtained. Aldosterone secretion rate was 89.6 +/- 25.8 (mean +/- SD)mug/day in normal subjects and was similar in low- and normal-renin essential hypertension. Significant high values (806.4 +/- 65.8mug/day) were obtained in primary aldosteronism and were slightly high in secondary aldosteronism and high-renin essential hypertension. The aldosterone secretion rate correlated positively with plasma aldosterone level (r = 0.731, p < 0.01). Aldosterone secretion rates were obviously higher than plasma levels in primary and idiopathic aldosteronism. From these results, it is concluded that this method is a very useful and reliable one for measuring aldosterone secretion rate and for discriminating primary aldosteronism from low-renin essential hypertension. it is superior in its simplicity, and there is no need to use a liquid scintillation counter.
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PMID:[A simple method for measuring aldosterone secretion rate using 125I-aldosterone (authors' transl)]. 741 29