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Presents a study that examined a normotensive woman who had already undergone bilateral renal arteriography and renal vein catheterization for differential renim production for her continuing hypokalemia. Emergence of diuresis and other conditions; Analysis of her urine; Consideration of the possibility of self-intoxication with diuretics to attain a slim figure.

Presents a case study of a patient with overproduction of aldosterone and suppressed plasma renin activity who proved to have bilateral modular adrenocortical hyperplasia. Background on aldosterone and cortisol secretion rate measurements; Clinical history of the patient; Details on the management of the condition.

A patient with primary hypothyroidism and pituitary gland enlargement was studies extensively before and after replacement therapy with levothyroxine sodium. She had evidence of bulging of the diaphragma sellae and increased serum prolactin levels. Thyroid replacement therapy resulted in regression of the pituitary size, as shown on pneumoencephalogram, but mildly elevated serum prolactin levels persisted.

A case of a 21-year-old woman with Cushing's disease due to a pituitary tumor is described. The patient was treated with cyprohepatadine for 4 weeks immediately following pituitary alpha-particle irradiation. A standard vasopressin test to measure ACTH-mediated cortisol release was performed four times: prior to pituitary irradiation, after irradiation, after 4 weeks of cyproheptadine therapy, and off cyproheptadine for 2 weeks. Cyproheptadine failed to modify vasopressin-stimulated cortisol release in the patient described. This study suggests that cyproheptadine, which has previously been shown to decrease ACTH secretion, probably acts principally at the hypothalamic, rather than at the pituitary level.

The changes in plasma renin activity (PRA) and plasma aldosterone concentration (PA) in response to postural stimuli were evaluated in 12 patients with stable diabetes mellitus and in five volunteers. Seven diabetic patients had hyperkalemia, and several had renal insufficiency and neurological complications. Five diabetics and had normal serum potassium concentration, a mean creatinine clearance within the normal range, and few complications. PRA and PA were measured in these patients and in the control subjects, all of whom were receiving a diet containing 10 mEq of sodium and 50 mEq of potassium while they were in a supine position, after they were tilted to a 90 degrees position, and after upright posture for two hours. The results indicate that impaired responsiveness of PRA and PA may occur in patients with complicated and those with uncomplicated diabetes and may be responsible in part for a relatively high prevalence of hyperkalemia especially in those diabetic patients with reduced renal function.

The effect of metabolic acidosis on the renin-aldosterone system remains unclear. In the present study anesthetized mongrel dogs (n = 19) were infused at similar rates with 0.45% NaCl (controls), HCl or NH4Cl (2.5mEq/kg) for 1--3 h. The induced metabolic acidosis in the two experimental groups was not associated with increases in plasma renin activity. Plasma cortisol (as a marker for ACTH secretion) and serum potassium concentration increased in both HCl- and NH4Cl-treated animals. Plasma aldosterone increased after 30 min in the HCl group and 60 min in the NH4Cl group and did not change in controls. These findings demonstrate that metabolic acidosis induced by HCl or NH4Cl is associated with increased aldosterone production without concomitant changes in plasma renin activity.

We describe 3 patients with metastatic medullary carcinoma of the thyroid who were treated with doxorubicin hydrochloride (Adriamycin). Serum calcitonin was measured before and after doxorubicin therapy. Doxorubicin failed to arrest the progression of the disease in any of the patients. Although serum calcitonin levels dropped in 1 patient during therapy, they remained markedly elevated in all 3 patients. From the present series it appears that medullary thyroid carcinoma often does not have a response to doxorubicin.

The metabolic clearance rates (MCR) of methylprednisolone (MP) (no. = 13) and methylprednisolone-21- Na-hemisuccinate (MPHS) (no. = 6) were studied in normal humans using tritium-labeled steroids. The cumulative appearance of the labeled steroid was examined for the whole urine and for three major urinary fractions. The MCR, half-life, and volume of distribution were, respectively, 383 +/- 72 (SD) liters/day, 165 +/- 49 minutes, and 61 +/- 12 liters for MP, and 234 +/- 37, 160 +/- 19, and 41 +/- 6 for MPHS. Diphenylhydantoin (DPH) administered to 4 subjects increased the MCR of MP from 424 +/- 71 to 977 +/- 132 (P less than 0.01), and decreased the half-life from 149 +/- 44 to 69 +/- 7 (P less than 0.001). Similar effects were found with phenobarbital (PB). Diazepam (DZP) had no effect. Major increases in urinary metabolites after DPH and PB were in the unconjugated ethyl acetate fraction, and this suggests that MP metabolism is significantly altered by hepatic microsomal hydroxylation enzyme induction by DHP and PB, but not DZP. This could occur with the formation of a 6beta-hydroxy derivative which could be readily cleared by the kidney. The urinary pattern of excretion for MPHS was similar to that of MP. The MCR of MPHS was affected to a lesser extent by DPH and PB than was the MCR of MP(P less than 0.01). Therefore, the use of hepatic microsomal hydroxylase inducers should be taken into consideration in clinical states in which MP is being used.

A post-ovulatory peak of fasting supine plasma aldosterone (PA) preceded or accompanied by an increase in plasma renin activity (PRA) was previously reported. These studies have now been extended in 4 additional normal menstruating women and 4 women taking oestrogen-progestogen oral contraceptive pills (OCP), all studied daily for an entire cycle. Distinct luteal phase increases in PRA were seen in the 4 normals, with 2 also demonstrating a rise in PA. Plasma renin substrate (PRS) was usually unvarying throughout the control cycles. The women taking OCP, on the other hand, all had PA and PRA peaks that were apparent by the fourth or fifth day of taking "the pill". All 4 of the treated women had elevated PRS levels but only one woman showed an increase which preceded the elevation of PRA and PA. Plasma cortisol levels were usually above the normal range in the women taking OCP. This study thus indicates that factors other than oestrogen-induced increased substrate production may be responsible for the PRA and PA rise during OCP treatment. Such factors might be the natri-uretic effects of oestrogens and progestogens or a direct effect on renin secretion by one of these steroids.

An infertile 27 year old man with precocious puberty is described. He presented in adulthood with unilateral and then bilateral gynecomastia, and subsequently testicular tumors developed. An early diagnosis of congenital adrenal hyperplasia would have avoided unnecessary surgery. Initial detailed metabolic evaluation led to the erroneous diagnosis of 11-hydroxylase deficiency because of the presence of an unusual steroid (21-desoxycortisol) in serum which was falsely reported as an increased 11-desoxycortisol (compound S). The observed low urinary pregnanetriol measurements would have supported this diagnosis. Subsequent specific measurements of 21-desoxycortisol established its presence in the serum and its major metabolite, tetrahydro-21-desoxycortisol, in the urine. The unique features in this case of 21-hydroxylase deficiency alert the physician to its unusual clinical presentation and the pitfalls that may be encountered when evaluating adrenal steroidogenesis.

The changes in plasma renin activity (PRA) and plasma aldosterone concentration (PA) in response to dietary sodium restriction and upright posture were evaluated in 7 patients with juvenile-type, insulin-dependent, uncomplicated diabetes mellitus and in 5 healthy volunteers. All patients had normal blood pressure, 24-hour urine protein excretion and endogenous creatinine clearance. Renal sodium conservation and concentrating ability were grossly normal and 5 patients so tested, had normal renal acidification. PRA and PA were normal in every subject suggesting that abnormalities of the renin-aldosterone axis are late complications of diabetes mellitus usually associated with hypertension and nephropathy or neuropathy.

4 patients with presumed pituitary hypothalamic sarcoidosis are described. 3 had histological diagnoses compatible with sarcoidosis and in the other this diagnosis was strongly suspected from chest X-rays. 2 patients presented with diabetes insipidus. ACTH reserve was diminished in 3 out of 4 and growth hormone reserve was diminished in the 3 who were tested. All 4 patients developed secondary amenorrhea. 3 patients had hypothalamic hypothyroidism. Prolactin dynamics were intact. Tomograms of the sella turcica in all 4 and computerized tomography of the hypothalamic area in 2 patients failed to reveal any abnormality.

Plasma renin activity and plasma aldosterone, supine and erect, and urinary aldosterone levels were measured in 18 patients on normal sodium diets and 11 patients on low sodium diets, all of whom also were on long-term levodopa therapy. Of the 230 hormone measurements, 185 were normal, 11 were high, and 34 were low. Most of the low levels were in 3 patients who had recently received fludrocortisone for orthostatic hypotension, and the renin-aldosterone systems might have been suppressed by it. In another phase of this study, 4 subjects were maintained on a constant diet for 6 wk, while the effect of gradually increasing dosages of levodopa on mineral balance and renin-aldosterone was determined. In 3 of the 4 patients there was a mild natriuretic effect of levodopa (previously demonstrated for acute levodopa therapy). There were no significant consistent changes in renin or aldosterone levels while levodopa was being administered. These studies indicate that levodopa does not usually suppress the elements of the renin-aldosterone system and that such a mechanism is unlikely to be the cause of orthostatic hypotension during the course of levodopa therapy. Since levodopa may induce natriuresis, in this situation unchanged lvels of renin and aldosterone may, however, represent an inappropriately low set of this hormonal system.

Plasma concentrations of vasopressin and plasma renin activity were measured every 30 min for 24 h in 5 normal active humans, in 1 normal woman confined to bed (except for brief periods up to the bathroom), in 2 active patients with primary aldosteronism and in 1 patient with low-renin hypertension. Plasma vasopressin varied markedly over the day and night in a pattern suggesting episodic secretion of the hormone in the normal subjects. Assumption of upright posture was accompanied by a rise in plasma levels from undetectable to 20--50 pg/ml. Episodic secretion, however, also occurred during bed rest and sleep. In contrast, patients with primary aldosteronism and low-renin hypertension had plasma vasopressin levels considerably lower than the normals, and their profiles of plasma concentration lacked the peaks seen in normals. In the normals, although vasopressin and renin secretion often coincided, only 2 of 6 studies showed a significant correlation between the plasma levels of the two hormones. This study, therefore, shows that vasopressin is secreted periodically in normal humans, that upright posture is an important modulator of secretory activity and that the renin-angiotensin system may or may not influence the pattern of secretion. In addition, it underlines the necessity of recumbency in establishing the existence of a circadian rhythm of plasma vasopressin levels.

Parotid fluid corticosteroids, substantially comprised of cortisol and cortisone, were previously demonstrated to rise to far greater levels 4 hr after administration of ACTH than they did in the third trimester of pregnancy, although the plasma total corticosteroid concentrations were similar in these two states. It was therefore suggested that only nonproteinbound corticosteroid gains access to parotid fluid. In the present study parotid fluid cortisol and cortisone and plasma dialyzable cortisol concentrations have been measured in normal men before and 2 hr after 40 U ACTH, and, in another group, before and after 10 days of diethystilbestrol (5 mg daily). Total plasma cortisol rose from a mean of 6.3 to 17.9 mug/100 ml after ACTH and from 14.6 to 39.4 mg/100 ml after the estrogen. However parotid fluid cortisol plus cortisone rose from 0.8 to 2.6 mug/100 ml after ACTH and to only 2.2 after estrogen. This rise resembled that of the plasma dialyzable cortisol (control 0.4, ACTH 1.8, estrogen 1.2 mug/100 ml) rather than the increase in total plasma cortisol which was over twice as high after estrogen as after ACTH. Thus parotid fluid corticosteroids seem to be a good measure of nonprotein-bound corticosteroid, the cortisol available to the cell. The total amount of cortisol plus cortisone excreted is approximately constant, independent of parotid fluid flow rate. Cortisone exceeds cortisol in parotid fluid in the basal state, but after ACTH the situation is reversed.

The effects of estriol and estradiol on the plasma levels of cortisol- and thyroxine-binding globulin activity, and on the secretion rates of aldosterone and cortisol were studied in man. The metabolite estriol had no consistent or significant influence on plasma levels of the hormone-binding globulin activities; the hormone estradiol increased these binding capacities significantly, as expected. Cortisol secretion rate rose slightly after estriol but was unchanged after estradiol. Both compounds induced substantial increases in the aldosterone secretion rate of most treated subjects. The mechanism of this apparently paradoxical effect of estrogens is not clear; it is suggested that the "salt-retaining" action of estrogens is mediated in part by the rapid enhancement of aldosterone output which follows their administration in man. Balance experiments in four subjects suggest that both estradiol and estriol may induce a transient early natriuresis in man; but other mechanisms for estrogen stimulation of aldosterone secretion may be operative as well.