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A 27-yr-old woman was referred for evaluation of acromegaly and hyperprolactinemia. She had undergone left adrenalectomy at 12 and right adrenalectomy at 17 for Cushing's syndrome due to adrenocortical nodular hyperplasia. At this time a pituitary tumor was found by brain computerized tomography, but plasma levels of growth hormone (GH), prolactin (PRL) and adrenocorticotropin (ACTH) were normal. When she was 23, symptoms and signs of acromegaly and subsequently galactorrhea-amenorrhea had developed. Plasma GH and PRL were increased and she was followed up by the administration of bromocriptine (2.5 mg-12.5 mg/day, p.o.). However the plasma GH level had been increasing gradually. On admission, plasma GH and PRL were high (19.5 micrograms/L, 61.0 micrograms/L, respectively) and increased in response to thyrotropin releasing hormone (TRH, 500 micrograms i.v.). An intrasella mass, which had been detected when she was 17, had become enlarged and was removed by Hardy's operation. Microscopically, the resected tumor was an eosinophilic adenoma. Immunohistochemical studies showed GH, PRL and ACTH positive cells localized in the tumor. Immunoultrastructural analysis of the tumor confirmed that GH, PRL and ACTH were present in secretory granules and Golgi apparatus in the tumor cells. The patient was a rare case of acromegaly with hyperprolactinemia developed after bilateral adrenalectomy of Cushing's syndrome due to adrenocortical nodular hyperplasia, all of which manifestations may be caused by a GH, PRL and ACTH secreting pituitary adenoma.

A 53-yr-old man with Cushing's disease was found to have a pituitary carcinoma with metastases to the liver and lung which produced both CRH and ACTH simultaneously. Despite removal of the pituitary tumor, his Cushing's disease worsened. Endocrinological examination then demonstrated elevated plasma CRH and markedly elevated plasma ACTH, beta-lipotropin, and cortisol concentrations, increased urinary 17-hydroxycorticosteroid and 17-ketosteroid excretion, and no suppression of serum cortisol after low or high dose dexamethasone administration. Urinary 17-hydroxycorticosteroid excretion increased in response to metyrapone, and lysine vasopressin elicited a striking increase in plasma ACTH. A computed tomographic scan of abdomen revealed multiple hypodense areas in the liver and bilateral adrenal hyperplasia. Postmortem histological examination revealed a necrotic hemorrhagic pituitary carcinoma with metastases to the liver, lung, and olfactory bulb. Immunohistochemical staining, gel filtration, and Northern blot analysis of liver and lung metastases revealed evidence of the production of both CRH and ACTH in these metastases. We concluded that the patient's pituitary carcinoma produced both CRH and ACTH.

The effects of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) on cortisol secretion by adrenocortical adenoma cells from patients with Cushing's syndrome (CS cells) in primary monolayer cultures, compared to cultured normal adrenal cells, were studied. alpha-hANP significantly inhibited cortisol secretion by human normal adrenal cells in culture, but had no direct effect on cortisol secretion from CS cells, in the presence or absence of 10(-8) M ACTH. alpha-hANP enhanced the accumulation of intracellular cyclic GMP in normal adrenal cells in culture, but not in CS cells. Visualization of [125I] iodo-alpha-hANP-specific binding sites by an in vitro receptor autoradiographic technique showed that these sites were lacking in adrenocortical adenoma tissues. These results suggest that the loss of alpha-hANP inhibitory effect on cortisol secretion in CS cells may be due to the absence of alpha-hANP receptor sites.

The pharmacological effects of synthetic alpha-human atrial natriuretic peptide (alpha-hANP) in patients with Cushing's syndrome and primary aldosteronism were compared with those in normal volunteers. An infusion of synthetic alpha-hANP at 0.1 microgram/kg per min for 20 min produced a maximal plasma hANP level of 800-1200 pg/ml in patients with Cushing's syndrome and primary aldosteronism, and in normal subjects. There were significant decreases in the mean blood pressure (-10 to -15 mmHg) in patients with Cushing's syndrome and primary aldosteronism, similar to those in normal subjects. The plasma cyclic 3'5'-guanosine monophosphate (cGMP) concentrations of both groups of patients were increased fivefold over the baseline level following the infusion. Infusion of synthetic alpha-hANP caused a greater increase in the rate of sodium excretion in patients with Cushing's syndrome and primary aldosteronism compared with normal volunteers. The plasma cortisol and aldosterone concentrations did not, however, significantly change during alpha-hANP infusion in either the patients with Cushing's syndrome or those with primary aldosteronism. As synthetic alpha-hANP has a potent hypotensive effect in hypertensive patients with Cushing's syndrome and primary aldosteronism, a significant reduction in blood pressure and natriuresis seems to occur without affecting adrenocortical steroidogenesis.

Glucocorticoid receptors (GR) in cultured fibroblasts obtained by forearm skin biopsy were characterized and GR in patients with hyper- and hypo-cortisolism were compared. Scatchard analysis of specific whole cell [3H]-dexamethasone binding showed a single class of high affinity receptors with a mean (+/- SD) binding capacity (R0) of 126,800 +/- 21,600 sites/cell and mean (+/- SD) apparent dissociation constant (Kd) of 2.9 +/- 0.4 nM in 6 normal subjects. Competition study of various steroids revealed that glucocorticoids were the most potent competitors. The order of the strength of competition was dexamethasone greater than betamethasone greater than prednisolone greater than hydrocortisone. Sucrose density gradient analysis revealed a specific 8.6 S binding peak in cytosol and 3.6 S in nuclear extracts. Dexamethasone showed the dose-dependent suppressive effect on thymidine incorporation. An inverse linear correlation between CI50 and % inhibition of thymidine incorporation by glucocorticoids was observed. There were no significant differences in parameters of whole cell GR among healthy controls, Cushing's disease (n = 4, R0 = 131,225 +/- 29,950/cell, Kd = 3.1 +/- 0.6 nM) and Addison's disease (n = 2, R0 = 131,600 +/- 25,600/cell, Kd = 3.2 +/- 0.2 nM). In one additional patient of hypercortisolism without clinical symptoms of Cushing's disease, R0 (144,000 +/- 12,960) was the same as control, but Kd (5.0 +/- 1.2 nM) was higher than the control.

We investigated the mechanism of dissociation of cortisol and dehydroepiandrosterone sulfate (DHEA-S) secretion by the adrenal glands after the removal of an adrenal gland containing an adrenocortical adenoma in a patient with Cushing's syndrome. After removal of the adrenocortical adenoma, the serum cortisol rapidly decreased from 24.6 +/- 6.4 micrograms/dl (mean +/- SD, n = 6) to 0.7 +/- 0.5 micrograms/dl. Serum DHEA-S levels were 15 +/- 14 micrograms/dl and 6 +/- 9 micrograms/dl before and after surgery, respectively, and significantly lower than the control values. Serum cortisol levels reverted to normal levels 1.5 to 3 years after the surgery. On the other hand, DHEA-S levels reverted to normal 5 to 7 years after the serum cortisol levels had normalized. Monolayer cultures of normal human adrenal cells obtained at adrenalectomy in patients with advanced breast cancer and atrophic adrenal cells adjacent to the adrenocortical adenoma in patients with Cushing's syndrome were used to study the mechanism of the dissociation of cortisol and DHEA-S secretion. ACTH caused significant increases in the productions of pregnenolone (P5), progesterone (P4), 17-hydroxypregnenolone (17-OH-P5), 17-hydroxyprogesterone (17-OH-P4), DHEA, DHEA-S, androstenedione (delta 4-A), and cortisol. The amounts of 17-OH-P5 and 17-OH-P4 produced by ACTH in atrophic adrenal cells were significantly greater than those in normal adrenal cells. The amounts of DHEA, DHEA-S and delta 4-A produced by ACTH in atrophic adrenal cells were significantly smaller than those of normal adrenal cells. The conversion rate of 17-OH-[3H]P5 to 17-OH-[3H]P4 and 11-deoxy-[3H] cortisol was higher in atrophic adrenal cells than in normal adrenal cells, but the conversion rate to [3H]DHEA, [3H]DHEA-S and [3H]delta 4-A was significantly lower in atrophic adrenal cells than in normal adrenal cells. These results suggest that the dissociation of cortisol from DHEA-S after the removal of adrenocortical adenoma is a probably due to diminished C17,20-lyase activity in the remaining atrophic adrenal gland.

In order to clarify the diurnal pattern of secretion of plasma immunoreactive (IR) proopiomelanocortin (POMC)-derived peptides, IR-N-terminal peptide (Nt), IR-beta-endorphin (Ep), IR-beta-lipotropin (LPH), and IR-ACTH (ACTH) in normal subjects and in patients with Addison's disease and Cushing's disease, we measured these 4 peptides in the same plasma obtained at 0900 h and then every three hours until 0600 h at the next day. All four peptides showed diurnal rhythms with the peaks at 0600 h, and the nadirs of ACTH, LPH, Ep and Nt were at 0000 h, 0000 h, 1800 h and 0300, respectively in normal subjects. In patients with Addison's disease, these four peptides also showed diurnal rhythms with the peaks at 0600 h for ACTH and Ep and at 0900 h for LPH and Nt, and the nadirs at 2100 h for ACTH and Ep and at 0000 h for LPH and Nt. The molar ratios of Ep/ACTH, LPH/ACTH and Nt/ACTH in plasma also presented diurnal variations in normal subjects and in patients with Addison's disease. On the other hand, in patients with Cushing's disease, ACTH, LPH and Nt showed no rhythmicity or change in molar ratios of Ep/ACTH, LPH/ACTH or Nt/ACTH. Only Ep showed diurnal variation. The molar ratios of Ep/ACTH, LPH/ACTH and Nt/ACTH in patients with Cushing's disease were significantly higher than those in normal subjects and in patients with Addison's disease at 0000 h.(ABSTRACT TRUNCATED AT 250 WORDS)