CUSHING'S SYNDROME

Sixteen cases of verified Cushing''s syndrome, and twelve cases of probable Cushing''s syndrome were reviewed and data on them were compared with various reports on Cushing''s syndrome in the literature.The diagnosis hinges upon a high index of suspicion, and one or several of the major criteria may be lacking.Ultimate establishment of correct diagnosis should be based largely on the clinical features, although stimulation and suppression tests may help to confirm a clinical diagnosis.In well-established clinical cases, with borderline laboratory confirmation, exploration may be justified, especially if tests fail to identify a specific cause.In cases of adrenal cortical tumor, all pathological tissue should be removed if possible, with great care to support and stimulate the remaining atrophic adrenal gland during and following operation.In cases of bilateral adrenal cortical hyperplasia, the problem is one of how much to remove. At present most investigators advocate radical subtotal resection, leaving less than 10 per cent of one side.     

A successful transplant of embryonic adrenal tissue in a patient with Addison's disease.

Well documented reports of the successful transplantation of human adrenal cortical tissue cannot be found in the literature. In 1951 we achieved the successful transplantation of human embryonic adrenal gland (cortical tissue) in a patient with symptomatic adrenal insufficiency (Addison''s disease), apparently the first instance of histologically documented successful homografting of human adrenal cortex. Because of its historical pertinence, the authors, many years later, herein report on this case, which appeared in the senior author''s medical thesis. The report must be viewed in the context of the existing clinical knowledge and technology available 40 years ago.     

Adrenocortical tumors

Hormonally active tumors of the adrenal cortex are either benign adenomas or adenocarcinomas. They may be located within the adrenal gland or as adrenal rests along the Wolffian tract. Hyperplastic cortical tissue without actual neoplastic formation is also capable of elaborating excessive cortical secretions.AT THE PRESENT STATE OF KNOWLEDGE, ANY ONE OR A COMBINATION OF THE FOLLOWING COMPOUNDS MAY BE ELABORATED IN A GIVEN CASE: the electrolytic, glucogenic, androgenic, or estrogenic corticosteroids. Whether or not Cushing's syndrome is primarily pituitary or adrenal in origin is still a matter of conjecture.     

ACTH inhibits the capsaicin-evoked release of CGRP from rat adrenal afferent nerves

The adrenal cortex is innervated by afferent fibers that have been implicated in affecting cortical steroidogenesis. Modulation of neurotransmitter release from afferents may represent a regulatory system for the control of adrenal cortical function. The present studies validate an in vitro superfusion technique for adrenal capsules employing the drug capsaicin, which activates a subset of afferent fibers and induces the release of calcitonin gene-related peptide (CGRP). Capsaicin-evoked CGRP release from adrenal afferents was blocked by capsazepine, a competitive antagonist for the capsaicin receptor, or by removal of extracellular calcium. Exogenous ACTH prevented capsaicin-evoked CGRP release, elevated basal aldosterone release, and prevented capsaicin-induced reduction in aldosterone release. Immunolabeling for the recently cloned capsaicin vanilloid receptor 1 demonstrated its presence in adrenal nerves. These results show that in vitro superfusion of adrenal capsules can be used to characterize factors that modulate neurotransmitter release from adrenal afferents. Furthermore, the results suggest that activation of adrenal afferents in vivo may attenuate aldosterone steroidogenesis and that high levels of ACTH may prevent this phenomenon.     

Adrenal cortical carcinoma: an unusual cause of hyperaldosteronism.

Although secondary hyperaldosteronism due to renal vein thrombosis may occur as a result of renal cell carcinoma or adrenal cortical carcinoma, primary hyperaldosteronism is rarely associated with the latter. This paper describes a patient with adrenal cortical carcinoma who presented with the clinical features of primary hyperaldosteronism 1 year after hypertension had been diagnosed; intravenous pyelography had not been done then. Drug therapy was ineffective, and the patient died 10 weeks after presentation.     

Immunoelectron microscopy pinpoints glutathione-peroxidase (GSH-PO) in neonatal rat adrenal cortical cells

Localization of glutathione-peroxidase (GSH-PO) in adrenal cortical cells of neonatal rats were determined by immunocytochemical analysis. GSH-PO first appeared 14 days after birth. Intracellular localization of GSH-PO was mainly in cytosol (cytosol GSH-PO) but no intramitochondrial localization of GSH-PO was detected. Twenty-one days after birth, intramitochondrial localization of GSH-PO (mitochondrial GSH-PO) was present. Mitochondrial GSH-PO depends on ACTH stimulation; therefore, its presence in the adrenal cortical cells of neonatal rats may be the morphologic expression of the gradual acquisition of adult metabolic features during steroidogenesis. The intracellular GSH-PO staining pattern in adrenal cortical cells therefore should be a useful marker for steroidogenesis.     

Bone mineral density in Addison's disease: evidence for an effect of adrenal androgens on bone mass.

It is unknown whether replacement doses of cortisone acetate and the absence of the small amounts of androgens secreted by the adrenal cortex may cause osteoporosis. This was studied in 35 patients (12 men and 23 women) suffering from primary adrenocortical failure and taking cortisone acetate 25-37.5 mg and fludrocortisone 50-100 micrograms daily. Bone mineral density was measured by single photon absorptiometry at the midshaft of the radius, representing cortical bone, and at the distal part of the radius, a site with a significant trabecular component. The bone mineral density was normal in premenopausal female patients as well as in male patients, showing that replacement doses of cortisone acetate do not affect bone mass. By contrast, in postmenopausal patients there was a dramatic bone loss in addition to the physiological postmenopausal decrease in bone mass. This loss, combined with the low plasma concentrations of androstenedione, dehydroepiandrosterone, and testosterone (and low concentrations of oestrone of adrenal origin), indicates that adrenal androgens may be essential for the maintenance of bone mass in postmenopausal women with Addison''s disease. In addition, these data indicate that the small amounts of androgens secreted by the adrenal cortex have a role in the maintenance of bone mass in normal postmenopausal women.     

Lack of an adrenal cortex in Sf1 mutant mice is compatible with the generation and differentiation of chromaffin cells

The diversification of neural-crest-derived sympathoadrenal (SA) progenitor cells into sympathetic neurons and neuroendocrine adrenal chromaffin cells was thought to be largely understood. In-vitro studies with isolated SA progenitor cells had suggested that chromaffin cell differentiation depends crucially on glucocorticoids provided by adrenal cortical cells. However, analysis of mice lacking the glucocorticoid receptor gene had revealed that adrenal chromaffin cells develop mostly normally in these mice. Alternative cues from the adrenal cortex that may promote chromaffin cell determination and differentiation have not been identified. We therefore investigated whether the chromaffin cell phenotype can develop in the absence of an adrenal cortex, using mice deficient for the nuclear orphan receptor steroidogenic factor-1 (SF1), which lack adrenal cortical cells and gonads. We show that in Sf1-/- mice typical chromaffin cells assemble correctly in the suprarenal region adjacent to the suprarenal sympathetic ganglion. The cells display most features of chromaffin cells, including the typical large chromaffin granules. Sf1-/- chromaffin cells are numerically reduced by about 50% compared with the wild type at embryonic day (E) 13.5 and E17.5. This phenotype is not accounted for by reduced survival or cell proliferation beyond E12.5. However, already at E12.5 the 'adrenal' region in Sf1-/- mice is occupied by fewer PHOX2B+ and TH+ SA cells as well as SOX10+ neural crest cells. Our results suggest that cortical cues are not essential for determining chromaffin cell fate, but may be required for proper migration of SA progenitors to and/or colonization of the adrenal anlage.     

Morphological evidence for a close interaction of chromaffin cells with cortical cells within the adrenal gland

Summary The adrenal medulla appears to exert a regulatory influence on adrenocortical steroidogenesis. We have therefore studied the morphology of rat, porcine and bovine adrenals in order to characterize the contact zones of adrenomedullary and adrenocortical tissues. The distribution of chromaffin cells located within the adrenal cortex and of cortical cells located within the adrenal medulla was investigated. Chromaffin cells were characterized by immunostaining for synaptophysin and chromogranin A, both being considered specific for neuroendocrine cells. Cortical cells were characterized by immunostaining for 17-hydroxylase, an enzyme of the steroid pathway. Cellular contacts of chromaffin cells and cortical cells were examined at the electron microscopical level. In rat and porcine adrenals, rays of chromaffin cells, small cell clusters and single chromaffin cells or small invaginations from the medulla could be detected in all three zones of the cortex. Chromaffin cells often spread in the subcapsular space of the zona glomerulosa. In porcine and bovine adrenals, 17-hydroxylase immunoreactive cells were localized within the medulla. Single cortical cells and small accumulations of cells were spread throughout this region. At the ultrastructural level, the chromaffin cells located within the cortex in pig and rat adrenals formed close cellular contacts with cortical cells in all three zones. Our morphological data provide evidence for a possible paracrine role of chromaffin cells; this may be important for the neuroregulation of the adrenal cortex.     

Adrenal Cortico-medullary Transplant with Antihypertensive Activity in the Rat

THE suspicion that the adrenal gland may possess an antihypertensive function rests on the observation that adrenal cortical extracts have antihypertensive activity in man and oppose hypertension induced by deoxycorticosterone in the rat^1,2. We have reasoned that if there is such a function, or a salt-losing role for the adrenal gland³, it is probably localized outside the zona glomerulosa. We have, therefore, carried out a series of transplantation experiments with potential autografts from the medulla and adjacent zona reticularis in the rat. Viable transplants have been produced and appear to have antihypertensive activity.     

Hypertension,Increased Aldosterone Secretion and Low Plasma Renin Activity Relieved by Dexamethasone

A father and son are described with a condition characterized by benign hypertension, potassium deficiency, increased aldosterone secretion rate (ASR), raised plasma volume and suppressed plasma renin activity (PRA). There were intermittent elevations of urine 17-ketosteroids and 17-hydroxycorticoids (17-OHCS) but no increase in urine THS, normal circadian rhythm of plasma 17-OHCS, and normal urine 17-OHCS response to dexamethasone and intravenous ACTH. Plasma ACTH and corticosterone secretion were not elevated. Pregnanetriol excretion was normal but urine pregnanediol was increased. At operation on the father no adrenal tumour was found; the excised left adrenal weighed 7 g. and showed nodular cortical hyperplasia; juxtaglomerular cells showed only occasional granules. Following operation hypertension persisted and ASR was half the preoperative value. All abnormalities in father and son were relieved by dexamethasone (DM) 2 mg. daily. The condition recurred following cessation of DM but was relieved by a second course of treatment. No such response to DM was seen in a normal subject or in a patient with Conn''s syndrome. For a number of reasons it is suggested that patients with hypertension, increased ASR and low PRA be given a trial of dexamethasone treatment before undergoing adrenal surgery.     

Operations on the adrenal glands

Various conditions of the adrenal gland are amenable to surgical treatment. Removal of a pheochromocytoma is almost always indicated when the tumor is diagnosed. The results of extirpation have been excellent in cases in which patients were operated upon before the onset of chronic hypertension. Removal of the "nerve cell" tumors of the adrenal is indicated if metastasis cannot be demonstrated. Hypofunction of the adrenal cortex may be partially alleviated by the repeated implantation of pellets of desoxycorticosterone acetate. Hyperfunction of the adrenal cortex causes a variety of clinical manifestations depending upon which of the numerous hormones are affected. Removal of a cortical tumor alleviates these symptoms. These tumors are malignant in more than 50 per cent of cases, and recurrence is frequent. Bilateral hyperplasia of the glands rather than a tumor may be present. In such circumstances, resection of 95 per cent of the adrenal tissue is effective in controlling the symptoms of the disease. Total bilateral excision of the adrenals is, at present, under investigation as a means of treatment for a variety of conditions.     

Iron exclusion by proliferative foci and neoplastic lesions induced by 7,12-dimethylbenz (a) anthracene in the rat adrenal cortex

Summary Proliferative and neoplastic adrenal cortical lesions were produced in female Sprague-Dawley rats by 7,12-dimethylbenz(a)anthracene. These lesions were studied for their ability to store histochemically demonstrable cellular iron compared with normal adrenocortical cells following iron loading by subcutaneous injection of iron-dextran. Stainable iron was excluded, under conditions in which normal cortical cells were heavily loaded with iron, in three histological types of adrenalcortical lesions; eosinophilic and basophilic proliferative foci; adenomas and lesions transitional between foci and tumours. The property of iron exclusion may be useful in studying neoplastic development in the adrenal gland.     

Steroidogenic activity of high molecular weight forms of corticotropin.

The high molecular weight forms of adrenocorticotropic hormone (ACTH) produced by mouse pituitary tumor cells (AtT-20/D-16v) were separated from each other by gel filtration; their ability to stimulate steroidogenesis by isolated rat adrenal cortical cells was studied. Pools of pro-ACTH/endorphin. ACTH biosynthetic intermediate, and glycosylated ACTH(1--39) were obtained; on the basis of NaDodSO4-polyacrylamide gel electrophoresis, over 97% of the immunoactive ACTH was found to have the expected molecular weight. Suspension of isolated rat adrenal cortical cells were incubated overnight in tissue culture medium and used in a 2-h steroid production assay. Synthetic human ACTH(1--39) [hACTH(1--39)] was used as a bioassay and immunoassay standard; 60 pM hACTH(1--39) stimulated half-maximal production of fluoregenic steroid. The amount of pro-ACTH/endorphin, ACTH biosynthetic intermediate, or glycosylated (ACTH(1--39) added was estimated with an ACTH(17--24) immunoassay. All three high molecular weight forms of ACTH are capable of stimulating the same maximal level of steroidogenesis as hACTH(1--39). Glycosylated ACTH(1--39) is equipotent with hACTH(1--39); ACTH biosynthetic intermediate and pro-ACTH/endorphin are, respectively, 100- and 300-fold less potent than hACTH(1--39). Steroid production in response to all four forms of ACTH is linear in time. All of the different forms of ACTH stimulate the synthesis of corticosterone and related steroids; no significant production of cortisol or aldosterone was observed. beta-Lipotropin (beta LPH) and 16K fragment, which comprise the non-ACTH regions of pro-ACTH/endorphin and are secreted by the pituitary tumor cells, did not stimulate or interfere with steroidogenesis. Brief incubations of pro-ACTH/endorphin and ACTH biosynthetic intermediate with trypsin generated lower molecular weight forms of ACTH and increased biological activity 50-fold; thus, the decreased steroidogenic potency of these forms of ACTH is thought to be due to structural constraints on the ACTH(1--39)-like sequence in these larger precursor molecules     

Molecular pathogenesis of lipoid adrenal hyperplasia and adrenal hypoplasia congenita

Congenital lipoid adrenal hyperplasia (lipoid CAH) is the most severe form of CAH in which the synthesis of all gonadal and adrenal cortical steroids is markedly impaired. Lipoid CAH may be caused by the defect in either the steroidogenic acute regulatory (StAR) protein or the P450scc. More than 34 different mutations in StAR gene have been identified. Clinically, most of the patients manifest adrenal insufficiency from 1 day to 2 months of age, but some patient show delayed onset of adrenal insufficiency. Affected 46, XY subjects do not show pubertal development, whereas affected 46, XX subjects undergo spontaneous feminization, breast development and cyclical vaginal bleeding at the usual age of puberty.

X-linked adrenal hypoplasia congenital (AHC) is a rare congenital adrenal disorder characterized by severe adrenal insufficiency and hypogonadotropic hypogonadism. More than 80 different several intragenic mutations of DAX-1 have been identified. The failure of pubertal development may be caused by either abnormal hypothalamic or pituitary regulation of gonadotropin secretion. In addition, although the testicular steroidogenesis is largely intact, the functional maturity of Sertoli cells and also spermatogenesis are impaired. The type of mutation does not predict clinical phenotype. Thus, unified mechanism how DAX-1 gene defect gives rise to adrenal insufficiency, hypothalamic/pituitary hypogonadism and impaired spermatogenesis remains established.     

TREATMENT OF ASTHMA: Somatic and Psychiatric

Various conditions of the adrenal gland are amenable to surgical treatment. Removal of a pheochromocytoma is almost always indicated when the tumor is diagnosed. The results of extirpation have been excellent in cases in which patients were operated upon before the onset of chronic hypertension. Removal of the “nerve cell” tumors of the adrenal is indicated if metastasis cannot be demonstrated.Hypofunction of the adrenal cortex may be partially alleviated by the repeated implantation of pellets of desoxycorticosterone acetate. Hyperfunction of the adrenal cortex causes a variety of clinical manifestations depending upon which of the numerous hormones are affected. Removal of a cortical tumor alleviates these symptoms. These tumors are malignant in more than 50 per cent of cases, and recurrence is frequent. Bilateral hyperplasia of the glands rather than a tumor may be present. In such circumstances, resection of 95 per cent of the adrenal tissue is effective in controlling the symptoms of the disease.Total bilateral excision of the adrenals is, at present, under investigation as a means of treatment for a variety of conditions.     

THE CLINICAL SIGNIFICANCE OF URINARY 17-KETOSTEROID ASSAYS

The urinary 17-ketosteroids are a group of compounds derived from complex steroids produced by the adrenal cortex, testis, or ovary. The method of determining the amount excreted has been simplified so that it is available for routine diagnostic purposes. Usually the amount is increased in diseases in which there is hyperfunction of the adrenal cortex due to tumor or hyperplasia, and decreased in lesions that impair the function of the adrenal cortex.Other conditions such as myxedema, eunuchism, gout, and arthritis may alter the excretion of the 17-ketosteroids. Low levels are also found in the young and in the aged. Case histories are presented to illustrate the findings in the following diseases: Tumors of the adrenal cortex with (a) masculinization, (b) Cushing''s syndrome with virilism and, (c) hirsutism; as well as in gigantism with acromegaly, in gout, eunuchism, Addison''s disease, myxedema, and severe panhypopituitarism.     

OPERATIVE AND POSTOPERATIVE EMERGENCY USE OF HYDROCORTISONE DERIVATIVES AND CORTICOTROPIN

Impairment of adrenal function is a great hazard to patients undergoing major operation. The most important adrenal steroids are glucocorticoids (hydrocortisone), 17-ketosteroids, mineralo-corticoids (aldosterone), and small amounts of estrogen and progesterone. Urinary output of 17-hydroxycorticoids reflects overall adrenal cortical activity. Under severe stress this output increases greatly.Adrenal replacement therapy is facilitated by the advent of more powerful and more soluble adrenal hormone derivatives. Hydrocortisone hemisuccinate sodium is the agent of choice in surgical emergencies and for management of bilateral adrenalectomy. Fatal adrenal crisis may develop during operation in patients receiving hydrocortisone for long periods of time. Hydrocortisone may be of help in unresponsive shock not due to loss of blood. The usual side effects of the corticoids can be controlled easily.     

Morphometric and histological studies on the adrenal glands of the camel Camelus dromedarius

The adrenal gland of the camel consists of an outer cortex and an inner medulla. The general disposition of the cortex and medulla, however, differs occasionally from that of other mammals. Extensions of medulla could reach as far as the periphery of the cortex. Islet of medullary tissue may be found in sections of the cortex and cortical tissue consisting of all zones of the cortex may occur around arteries or nerves in the medulla. The medulla may be separated from the cortex by connective tissue especially in old camels. The arrangement of noradrenaline-secreting cells is different from that in other ruminants; they are found in groups scattered between the adrenaline-secreting cells. Bundles of smooth muscle occur in venules at the corticomedullary interface. Accessory adrenal glands are found embedded in the renal fat. They are similar in structure to the adrenal gland. The adrenal cortex forms 74% of the volume of the gland and the ratio of the cortex to medulla is 4:1. The zona glomerulosa, fasciculata and reticularis constitute about 13%, 53%, and 29% by volume of the cortex, respectively.