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C Gomez-Sanchez

Publications and source records attributed to C Gomez-Sanchez.

44 records · Page 3Linked to original sources
PubMed1975

A direct radioimmunoassay of corticosterone in rat serum.

A direct radioimmunoassay of corticosterone is described requiring as little as 1-2 mul of rat serum. After methanol inactivation of CBG, serum was assayed with a relatively specific antibody raised against corticosterone-21-hemisuccinate. While this antibody has a significant cross-reaction with cortisol, prior purification is not necessary since cortisol is not produced in the rat.

Animals↗
PubMed1975

Isolation and characterization of 5alpha-pregnane-3,20-dione and progesterone in pepipheral blood of pregnant women. measurement throughout pregnancy.

5alpha-Pregnane-3,20-dione and progesterone were isolated from a pregnancy plasma pool and were identified by using a combination of chromatographic techniques and mass spectrometry. Antibodies to progesterone were obtained in rabbits by immunization with progesterone-1alpha-carboxyethyl-thioether-thyroglobulin. The raised antibodies were of high affinity and one of them cross-reacted (137%) with 5alpha-pregnane-3,20-dione. This property was used to develop radioimmunoassays for measuring circulating levels of both progesterone and 5alpha-pregnane-3,20-dione in pregnancy plasma. The levels of both progesterone and 5alpha-pregnane-3,20-dione increase throughout pregnancy, but a highly significant increase is observed only after the 32nd week of gestation.

Animals↗
PubMed1975

The effect of dexamethasone on the control of plasma aldosterone concentration in normal recumbent man.

In order to evaluate the control of the circadian rhythm of plasma aldosterone concentration in man, plasma aldosterone, cortisol, sodium and potassium concentrations, and plasma renin activity (PRA) were measured in samples obtained at 20-minute intervals from 0200 to 0800 in sodium repleted (180 mEq. per day of diet) and sodium depleted (22 mEq. per day of diet) normal subjects. During sodium replete studies, plasma aldosterone and cortisol concentrations were significantly correlated (p greater than 0.01) in all 4 subjects. Plasma aldosterone also correlated with PRA (p greather than 0.01) in 2 subjects and with potassium (p greater than 0.01) in one. Episodic increases in plasma aldosterone concentration were observed despite suppression of ACTH by dexamethasone treatment. Plasma aldosterone concentrations were significantly correlated with PRA (p greater than 0.05 and p greater than 0.01) in only 2 of 4 subjects under these conditions. Following sodium restriction, plasma aldosterone concentrations were not significantly correlated with plasma cortisol and only infrequently with either PRA or potassium. When dexamethasone was administered during the low sodium diet, correlations with PRA (p greater than 0.001) were seen in 2 of 3 subjects and with potassium (p greater than 0.01) in 1 of 3 subjects. There was no significant correlation between plasma aldosterone and sodium concentration during any of the studies. These results are compatible with the concept that the relative importance of PRA, ACTH, and potassium in inducing changes in aldosterone production during the early morning hours is partially dependent upon dietary sodium, but also varies between individuals studied during similar sodium diets. The episodic alterations of plasma aldosterone concentration continued after ACTH was suppressed by dexamethasone pretreatment. These changes, in the absence of a consistent significant correlation with PRA and sodium and potassium concentrations, further suggest that another factor(s) may be important in controlling aldosterone production in recumbent normal subjects.

Administration, Oral↗
PubMed1973

Circadian rhythm of plasma aldosterone concentration in patients with primary aldosteronism.

Plasma aldosterone, cortisol, and renin activity were measured in nine recumbent patients with hyperaldosteronism, including seven with adenomas, one with idiopathic hyperplasia, and one with glucocorticoid suppressible hyperplasia. All had peak values of plasma aldosterone concentration from 3 a.m. to noon and lowest values at 6 p.m. or midnight. This rhythm was similar to the circadian pattern of plasma cortisol in the same patients. When these data were normalized to eliminate the wide variation in ranges of plasma aldosterone and cortisol between individuals, there was an excellent correlation (r = + 0.87, P < 0.005) between the two hormones. In contrast, plasma aldosterone concentrations did not correlate with plasma renin activity before or after normalization of data. Short term suppression of ACTH by administration of dexamethasone eliminated the circadian variation of plasma aldosterone in both patients with hyperplasia and in four of five patients with adenomas, while it markedly altered the rhythm in the fifth. Similar doses of dexamethasone were administered to four normal subjects and did not flatten the circadian rhythm of plasma aldosterone. These data suggest that patients with primary aldosteronism have a circadian rhythm of plasma aldosterone mediated by changes in ACTH.

Adenoma↗