Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationship of plasma aldosterone concentration to its identified stimuli was examined in three patients with hypertension, hyperaldosteronism, and idiopathic adrenal hyperplasia. Four patients with hyperaldosteronism due to adrenal adenomas served as controls. Plasma aldosterone, cortisol, sodium, and potassium concentrations and renin activity were measured in blood samples taken at 20 minute intervals from 2 A.M. to 8 A.M. during recumbency and sleep. The tests were performed on all patients following a regular sodium diet both before and after short-term treatment with dexamethasone. Two of the three subjects with adrenal hyperplasia were re-examined after 2 weeks of dexamethasone therapy. All four control patients with adenomas had episodic increases of plasma aldosterone which were significantly correlated with those of plasma cortisol (r = +0.48 to +0.90). This confirms the previously reported relationship between aldosterone and ACTH in such patients. Two patients with idiopathic adrenal hyperplasia had a similar secretion pattern and a highly significant correlation of the two hormones (r = +0.76 and +0.77); one did not (r = 0.13). Short-term dexamethasone pretreatment attenuated the episodic release pattern and partially suppressed the mean plasma concentrations of aldosterone in the four patients with an adenoma and in the two patients with idiopathic hyperplasia whose plasma aldosterone and cortisol concentrations were positively correlated. There was no such effect in the third patient. The first two patients with idiopathic hyperplasia were subsequently retested following 2 weeks of dexamethasone treatment to determine if the episodic secretion pattern of plasma aldosterone would correlated with other stimuli following this period of ACTH suppression. One showed little change from the pattern observed after short-term glucocorticoid treatment. The second had a similarly blunted aldosterone response until ACTH secretion led to a resumption of episodic changes in plasma aldosteerone concentrations. These data indicate that ACTH frequently is the dominant stimulus of the episodic secretion of aldosterone in patients with either adrenal adenomas or hyperplasia. When ACTH is suppressed, the hypersecretion of aldosterone is presumably sustained by an intrinsic adrenal abnormality or by an as yet unidentified stimulus.
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PMID:The role of ACTH in the episodic release of aldosterone in patients with idiopathic adrenal hyperplasia, hypertension, and hyperaldosteronism. 18 90

In 31 patients with primary aldosteronism routine clinical and laboratory data, the effect of orthostasis on plasma aldosterone (PA), plasma renin activity (PRA) and cortisol (PC), effect of fludrocortisone or high sodium intake on basal PA and night-day fluctuations of basal PA and PC with and without suppression of pituitary ACTH by dexamethasone were determined to differentiate patients with a unilateral aldosterone producing tumour (adenoma, APA, n=20; carcinoma, CA, n=1) from those with idiopathic bilateral adrenal hyperplasia (IAH, n=10). Mean systolic and diastolic blood pressure, age, serum potassium and urinary excretion of sodium and potassium were not significantly different in both groups of patients. Normokalaemic primary aldosteronism occurred both in patients with APA (n=2) and in patients with IAH (n=1). Mean basal PA and mean urinary excretion rate of aldosterone-18-glucuronide were higher though not significantly different in patients with APA or CA than in those with IAH. A substantial number of the patients with APA (n=5) and with IAH (n=3) showed urinary excretion rates of aldosterone-18-glucuronide less than 13 microgram/24 h. Mean PA and PRA significantly increased (P less than 0.025) in patients with IAH in response to posture. However, these changes also occurred at times in some patients with APA. Both fludrocortisone and high sodium intake produced a variable and no group-specific effect on basal PA. Night-day variations in PA were positively correlated with those in PC in all patients with APA (n=12) and in 5 of 8 patients with IAH. A dissociation of PA and PC, however, was only observed in patients with IAH. Finally, the effect of dexamethasone on plasma aldosterone curves was variable in both groups of patients. Our results indicate that under the described conditions analysis of routine clinical and laboratory data and of peripheral PA, PRA and PC are of limited value in differentiating patients with APA or CA from those with IAH.
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PMID:Primary aldosteronism: inability to differentiate unilateral from bilateral adrenal lesions by various routine clinical and laboratory data and by peripheral plasma aldosterone. 21 20

1. Noradrenaline and adrenaline in the adrenal vein of essential hypertensive patients are almost exclusively (99%) unconjugated or free. However only 17% of dopamine is free, the rest is conjugated. The further the site of sampling from the adrenal vein the closer come the free catecholamines to their normal peripheral venous proportion (noradrenaline + adrenaline 20%, dopamine less than 1% of total catecholamines). Deviations from these patterns help to detect the site and type of secretion of phaeochromocytoma. 2. Essential hypertensive patients have, compared with control subjects, higher conjugated plasma dopamine, less urinary free and conjugated dopamine with blunted urinary free dopamine and sodium responsiveness to frusemide. Conjugated noradrenaline + adrenaline, mean arterial pressure and age are positively interrelated. 3. Patients with primary aldosteronism have elevated plasma and urinary total dopamine. After removal of the adenoma urinary dopamine excretion decreases to normal. 4. Elevated conjugated dopamine appears to reflect a compensatory activation of the dopaminergic vasodilator pathway in hypertension, the total urinary dopamine excretion an intrinsic deficiency or compensatory increase of a dopamine-modulated natriuretic mechanism.
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PMID:Free and conjugated catecholamines in human hypertension. 28 3

1. Amiloride (40 mg/day) was given to nineteen patients with primary hyperaldosteronism. There were significant falls in systolic and diastolic blood pressure, in total exchangeable sodium and in serum sodium and bicarbonate, while total exchangeable potassium, total body potassium, serum potassium, chloride and urea, plasma renin, angiotensin II and aldosterone all increased significantly. Amiloride was effective in reducing the blood pressure in patients with and without adrenocortical adenoma. No carry-over effect was seen on withdrawing amiloride. Similar changes were associated with amiloride treatment in five patients with essential hypertension; hyperkalaemia was not observed. 2. Only negligible side effects were encountered in the entire series of 24 patients.
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PMID:Amiloride in the treatment of primary hyperaldosteronism and essential hypertension. 35 30

Sodium nitrite has been widely used as one of the most effective food additives to tinge color on cured meat. However, it has been elucidated that this chemical is not merely a precursor of N-nitroso compounds, many of which are strongly carcinogenic, but also a mutagenic substance in biological tests. In order to ascertain the possible tumorigenicity of sodium nitrite itself, chronic toxicity of the agent in mice, by means of daily oral administration as drinking water for more than 18 months, in the concentration of 0.5 (maximum tolerated dose), 0.25, and 0.125%, was tested. As a result, development of various tumors, including thymic lymphoma, nonthymic lymphoid leukemia, pulmonary adenoma and carcinoma, and benign and malignant tumors in soft tissue, was seen in these mice. However, as to the incidence of tumors as well as the developmental time of each histologically classified tumor, no apparent difference was detected between those in the experimental groups and the control group.
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PMID:Chronic toxicity of sodium nitrite in mice, with reference to its tumorigenicity. 46 85

Plasma aldosterone levels and the serum electrolytes potassium, sodium and magnesium of 38 patients with healthy adrenals were determined. Under physiological conditions there were no significant correlations between these parameters. In two patients with an aldosterone producing adenoma of the adrenals (syndrome of Conn) we found very low levels of potassium and low levels of magnesium. The levels of sodium lay in the upper normal range. Plasma aldosterone levels are raised strongly. After resection of the tumors the mentioned parameters normalized. In 16 patients with cirrhosis and ascites we generally found values of aldosterone, potassium, sodium and magnesium which lay in the lowest normal range. Under treatment with spironolactone the aldosterone levels raised and reached values which are characteristical of the syndrome of Conn. Potassium raised to the upper normal range, magnesium raised significantly, sodium diminished slightly.
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PMID:[Plasma aldosterone and electrolytes in primary and secondard aldosteronism (author's transl)]. 49 54

Serial measurements of urinary sodium excretion, sodium space, plasma volume, and plasma renin concentration were made during the development of hypertension in patients who were exposed to an excess of endogenous or exogenous mineralocorticoid activity. Five patients with primary aldosteronism due to adenoma were followed during spironolactone treatment, for 35-55 days after the drug had been stopped, and finally, after surgery. Blood pressure rose continuously after stopping spironolactone. Sodium balance, however, showed an initial phase of sodium gain, followed by a phase of gradual sodium loss. Sodium space and exchangeable sodium rose by 5.0 +/- 0.48 liters/1.73 m2 of body surface area (BSA) (P less than 0.005) and by 865 +/- 97 mEq/1.73 m2 BSA (P less than 0.005), respectively; the values were maximal after 10-15 days, declined afterward, but remained higher than during spironolactone treatment. Plasma and blood volumes rose by 624 +/- 90 ml/1.73 m2 BSA (P less than 0.005) and by 327 +/- 74 ml/1.73 m2 BSA (P less than 0.01), respectively; they were maximal after 20-25 days, and then returned to their initial values. Exchangeable sodium, during the phase of sodium loss, was inversely correlated with the rise in blood pressure (P less than 0.01). Renin fell during the phase of sodium gain, and remained low afterwards. Blood pressure and sodium space declined after surgery, but plasma volume showed no change. The postsurgery values of these parameters were not significantly different from those measured during spironolactone treatment. Two subjects with adrenocortical insufficiency, who were followed for 45-60 days during treatment with dexamethasone and 9alpha-fluorocortisol acetate, also showed a transient rise in sodium space and plasma volume. The results suggest a redistribution of body fluids during development of hypertension. They also suggest that the tendency of body fluid volumes to return to normal is pressure-dependent. The long-term effects of mineralocorticoid excess on the interrelations between pressure, volume, and renin bear some resemblance to the pattern observed in patients with established essential hypertension, i.e., pressure remains elevated despite a decrease of volume, and renin is "inappropriately" suppressed in relation to the sodium and volume status.
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PMID:Volume-pressure relationships during development of mineralocorticoid hypertension in man. 85 75

Among the atypical pictures of primary aldosteronism, sometimes, normal blood and urine concentration of aldosterone have been observed in association with an adrenal aldosterone-producing adenoma. Here we report a case of atypical primary aldosteronism so characterized: -- the patient had the typical clinical findings of aldosteronism (hypertension, hypokalemic alkalosis, polyuria, etc). -- the patient exhibted all the biochemical abnormalities of primary aldosteronism: increase of exchangeable Na and of plasma volume, decrease of exchangeable K, etc. -- the patient had normal blood and urine levels of aldosterone. -- the patient's blood and urine aldosterone concentration increased following sodium depletion and K administration. Such increase was comparable with that obtained in normal subjects after the same tests. However, at the end of these tests, the patient was still in potassium depletion and sodium repletion. Therefore, it was concluded that the secretion of aldosterone, although normal in absolute values, was inappropriate to the metabolic status of the patient, since such "normal" values were found in association with conditions that should have produced an inhibition of aldosterone production. The catheterization of adrenal veins demonstrated the existence of a right adrenal adenoma. The blood pressure and the biochemical parameters of the patients have been normalized by right adrenalectomy.
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PMID:[Physiopathological and functional semeiologic considerations in a case of primary normoaldosteronemic hyperaldosteronism]. 88 97

Amiloride (40 mg/day) was given to nineteen patients with primary hyperaldosteronism. There were significant falls in systolic and diastolic blood pressure, in total exchangeable sodium, and in serum sodium sodium and bicarbonate; while total exchangeable potassium, total body potassium, serum potassium, chloride and urea, and plasma renin, angiotensin II and aldosterone all increased significantly. Amiloride was effective in reducing blood pressure in patients with and without adrenocortical adenoma. No carry-over effect was seen on withdrawing amiloride. Similar changes were associated with amiloride treatment in five patients with essential hypertension; hyperkalaemia was not observed. Only negligible side-effects were encountered in the entire series of twenty-four patients.
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PMID:Amiloride in the treatment of primary hyperaldosteronism and essential hypertension. 89 Sep 99

In a prospective study of 7 patients with aldosterone-producing adenoma (APA), long-term (6-72 months) preoperative stimulation of plasma renin activity (PRA) by diuretic therapy (spironolactone plus hydrochlorothiazide) did not prevent selective aldosterone deficiency postoperatively. In all patients aldosterone excretion rate (AER) fell to subnormal values (from a mean of 97 to 2.6 mug/24 h) following removal of APA, although PRA remained elevated. Generalized adrenocortical insufficiency was excluded by the demonstration of normal baseline plasma cortisol and urinary 17-OHCS and the appropriate response to ACTH stimulation. In 6 of 7 patients studied 1-3 months postoperatively, short-term (4 days) sodium deprivation evoked normal increases in PRA, but AER response was blunted (except in 1). Restudy of 3 of 6 patients after 6-12 months revealed that aldosterone production had returned to normal. These results indicate that renin deficiency is not the principal cause of postoperative selective hypoaldosteronism in these patients. On the other hand, they appear to substantiate the possibility raised by in vitro and in vivo studies that spironolactone can directly inhibit aldosterone biosynthesis.
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PMID:Selective hypoaldosteronism despite prolonged pre- and postoperative hyperreninemia in primary aldosteronism. 115 65


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