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We report a patient with Cushing's syndrome in whom the etiology of the hypercortisolemia could not be definitely established despite extensive biochemical investigations. Results included raised basal serum cortisol, plasma ACTH, and urinary free cortisol; failure to suppress even a paradoxical rise in serum cortisol after dexamethasone (1 mg overnight, 2, 8, and 16 mg/day); and a definite but not exaggerated rise in 11-deoxycortisol after metyrapone. After iv CRF, plasma ACTH rose from 22 to 30 pmol/L. Abdominal computed tomographic scanning showed adrenal hyperplasia; the presence of an adrenal adenoma, although suspected, was not established. An unusual finding was the presence in the urine of large amounts of 21-deoxycortisol metabolites, including 3 alpha,11 beta,17 alpha-trihydroxy-5 beta-pregnan-20-one and 5 beta-pregnane 3 alpha,11 beta,17 alpha,20 alpha-tetrol. On the basis of preoperative biochemical/radiological findings, a provisional diagnosis of ACTH-dependent Cushing's syndrome associated with autonomous bilateral adrenal hyperplasia was made. Incomplete bilateral adrenalectomy was performed; adrenal hyperplasia was histologically confirmed, but no tumor was found. However, ACTH was measured 1) just before operation when the patient was receiving treatment with metyrapone, and 2) postoperatively when the patient was receiving steroid replacement only, and on these occasions ACTH levels were lower than during the initial investigations. Pituitary scans before and after adrenalectomy were similar, offering no evidence of pituitary infarction. We propose that abnormal production of 21-deoxycortisol contributed to the aberrant regulation of ACTH and cortisol in this case, providing an example of a previously unreported cause of hypercortisolemia.

Immunoreactive plasma levels of the proopiolipomelanocortin-derived peptides, ACTH, beta-endorphin-lipotropin, and gamma 3MSH, were measured in patients with primary hyperaldosteronism, idiopathic hyperaldosteronism with bilateral adrenal hyperplasia, and dexamethasone-suppressible hyperaldosteronism. Plasma peptide concentrations in patient groups were not different from those in normal controls. Removal of aldosterone-producing adenomas in three patients and of an aldosterone-producing adrenocortical carcinoma in one patient did not affect plasma peptide concentrations. Furthermore, infusion of the opiate antagonist naloxone (0.2 mg/min) in one patient with bilateral adrenal hyperplasia had no effect on either plasma aldosterone or cortisol. These results suggest that the proopiolipomelanocortin-derived peptides are not overproduced in states of hyperaldosteronism.

Plasma testosterone (T) and dihydrotestosterone (DHT) were measured in the plasma of otherwise healthy men ages 60-90 who had prostate hyperplasia. The androgens were measured by specific radioimmunoassays using paper and celite column chromatography. In the elderly subjects, plasma T was 466+/-35 (SE) ng per 100 ml which is reduced (p less than 0.05) as compared with values from younger men. In contrast, DHT levels were elevated when compared with values from men ages 20-39, 89 (53-152) versus 49 (33-74) 95% confidence ng per 100 ml. Analysis of data by the Mann Whitney U test demonstrates that the groups are different (p less than 0.001). These studies indicate that DHT levels and T/DHT ratios are altered in unstressed elderly men with BPH. Further study is necessary to delineate the source of DHT and whether these altered androgen levels are the cause of prostate hypertrophy or an unrelated effect of aging.

Ovarian secretion of testosterone and androstenedione is increased in postmenopausal women with endometrial cancer, and insulin stimulates ovarian stromal androgen synthesis in vitro. We undertook this study to investigate whether women with endometrial cancer have increased serum immunoreactive insulin levels. Ten postmenopausal women with endometrial carcinoma and 10 postmenopausal women without cancer who matched the cancer patients in age, years since menopause, and percentage of ideal body weight were studied. The women with endometrial cancer had significantly higher fasting serum insulin levels than the normal women [mean, 187 +/- 26 (+/- SE) vs. 55 +/- 11 pmol/L; P less than 0.01]. The cancer patients had significantly higher insulin responses after glucose administration than normal women (sum of 1, 2, and 3 h postglucose values, 5545 +/- 1526 vs. 1444 +/- 156 pmol/L; P less than 0.02), even though their glucose responses were similar. Nests of luteinized cells, which were positive for testosterone by immunoperoxidase staining, were found in the ovarian stroma of 8 of the women with endometrial cancer, but in only 1 of those without cancer (P less than 0.01). Specific high affinity insulin receptors were demonstrable in the stroma of the postmenopausal ovaries. These results suggest that the frequency of stromal luteinization is increased in women with endometrial cancer and that insulin may play a role in the pathogenesis of this luteinization.

Serum 18-hydroxycorticosterone, aldosterone, and potassium were measured under basal conditions in 34 patients with documented primary aldosteronism, 10 patients with essential hypertension, and 9 normal subjects. The results revealed that 22 of 23 patients with aldosterone-producing adenomas had 18-hydroxycorticosterone levels greater than 100 ng/dl, and all 9 patients with idiopathic adrenal hyperplasia had plasma levels less than 100 ng/dl. Two patients with unusual macromicronodular hyperplasia of the adrenal glands had levels greater than 100 ng/dl. We found a significant relationship between serum potassium and the ratio of 18-hydroxycorticosterone to aldosterone in patients with idiopathic adrenal hyperplasia, but not in those with an aldosterone-producing adenoma. We conclude that measurement of serum 18-hydroxycorticosterone is a useful predictor of the etiology of primary aldosteronism.

Clinical and biochemical findings in 13 patients (11 women and 2 men) with macronodular adrenocortical hyperplasia (MNH; nodule size, greater than 0.5 to 5.3 cm) were compared with those of 18 patients (15 women and 3 men) with Cushing's disease and diffuse (n = 9) or micronodular (n = 9) hyperplasia (DH). All were bilaterally adrenalectomized for their hypercorticism. The clinical picture was almost identical in both groups, except for greater frequency of hypertension (13 of 13 vs. 10 of 18; P less than 0.05), alopecia (4 of 11 vs. 0 of 15; P less than 0.05), and scintigraphic lateralization (6 of 7 vs. 1 of 7; P less than 0.05) in the MNH group than in the DH group. The sella turcica was enlarged in 30% of the patients in both groups. Patients with MNH were significantly older than DH patients [43.5 +/- 7.8 (mean +/- SD) vs. 31.7 +/- 10.1 yr; P less than 0.005] and had a 3-fold longer duration of disease (7.8 +/- 4.6 vs. 2.0 +/- 1.1 yr; P less than 0.001) than those with DH. The mean plasma ACTH and cortisol levels and urinary 17-hydroxycorticosteroid excretion were elevated in both MNH and DH patients and responded similarly to specific (corticotropin-releasing hormone and metyrapone) and nonspecific (TRH and LHRH) stimuli. However, dexamethasone suppressibility and the stimulatory effect of ACTH on adrenocortical function were less in the MNH than in the DH group or its subgroups, suggesting a greater degree of adrenal autonomy in the former. Adrenal weight in MNH (15.8 +/- 12.1 g each) was almost twice as high as in DH (8.2 +/- 2.0 g) patients and positively correlated with the duration of the disease. The data suggest that MNH may be a result of long-standing Cushing's disease with varying degrees of pituitary dependence and adrenocortical autonomy, which may lead to confusing biochemical and radiological findings. Bilateral adrenalectomy, rather than hypophysectomy, is the treatment of choice in MNH.

To examine possible feedback inhibition of insulin on proinsulin secretion, we measured serum proinsulin levels before and after 120 min of euglycemic hyperinsulinemia (90-100 mU/liter) in 11 normal and 7 obese hyperinsulinemic subjects and 6 patients with beta-cell adenoma (n = 4), carcinoma, or hyperplasia. Baseline proinsulin levels accounted for 19%, 14%, and 56% of the total immunoreactive insulin in the 3 groups, respectively. Compared to normal subjects, baseline proinsulin levels were elevated (P less than 0.02) by 4- and 6-fold in obese subjects and patients with autonomous insulin secretion, respectively, but there was an overlap between the groups. In both normal and obese subjects, hyperinsulinemia suppressed proinsulin secretion by 45-50% (P less than 0.02), whereas no response occurred in the patients. Thus, the 120 min values were clearly different in the patients and the normal or obese subjects. After removal of the adenoma in 4 patients, baseline proinsulin levels and the response to hyperinsulinemia were normalized, but they remained elevated after a partial pancreatectomy or tumor removal in the patients with beta-cell hyperplasia or carcinoma. Thus, proinsulin secretion is under negative feedback control of insulin in both normal man and hyperinsulinemic obese subjects. In patients with insulinoma or beta-cell hyperplasia, this control is lost.

Plasma Aldosterone (PA) response to metoclopramide (10 mg i.v.) was studied in 11 normal, 2 hypophysectomized subjects and in one patient with bilateral adrenal hyperplasia. All the subjects were kept on a normal sodium and potassium intake. Four normal subjects were pretreated with 1 mg of dexamethasone in order to inhibit endogenous ACTH. In all subjects metoclopramide elicited a prompt rise of PA comparable to that obtained with angiotensions or ACTH. No significant change of blood pressure, serum electrolytes, plasma renin activity, Plasma Cortisol (PC) was detected. The lack of PC response to metoclopramide and the PA increase in dexamethasone pretreated subjects rule out an ACTH mediated effect. The increase of PA in hypophysectomized subjects, in whom metoclopramide did not stimulate any prolactin release, rules out a prolactin mediated effect. Metoclopramide increases plasma aldosterone concentration probably via a direct action on the adrenal glomerular zone or throught another unknown mechanism.