Cushing’s Syndrome in a Patient with Bilateral Macronodular Adrenal Hyperplasia Responding to Cisapride: An in Vivo and in Vitro Study

ObjectiveAberrant adrenal expression of various hormone receptors has been identified in ACTH-independent macronodular adrenal hyperplasia (AIMAH) causing cortisol hypersecretion regulated by hormones other than ACTH. We aimed to determine aberrant expression of multiple hormone receptors in vivo and in vitro in adrenal tissue of a patient with AIMAH.DesignThe design of the study includes clinical case description, and biochemical and immunohistochemical analysis to demonstrate aberrant expression of multiple hormone receptors in AIMAH.MethodsThe subject of the study is a male diagnosed with Cushing's syndrome because of AIMAH. Directly after laparoscopic removal of the adrenals, adrenal tissue was incubated with and without test substances (ACTH, forskolin, arginine vasopressin (AVP), desmopressin, epinephrine, norepinephrine, purified human chorionic gonadotropin (hCG), metoclopramide and the combinations of AVP with ACTH, epinephrine and metoclopramide). LH/hCG-receptor (hCG-R) immunohistochemistry and RT-PCR analyses were performed to demonstrate aberrant expression of LH/hCG-R and V1–3-AVPR.ResultsAIMAH was characterized by in vivo cortisol responsiveness to AVP and in vitro cortisol responses to AVP, hCG, epinephrine, and norepinephrine suggesting aberrant adrenal expression of the receptors for AVP (the V1–3-AVPRs), catecholamines (the β-AR), and LH (the LH/hCG-R). Incubation with combinations of AVP and ACTH and of AVP with epinephrine induced a stronger cortisol response compared with incubation with the individual agents. Moreover, we demonstrated adrenal V1–3-AVPR and LH/hCG-R expression.ConclusionsAIMAH tissue may simultaneously express multiple aberrant hormone receptors, and individual ligands may potentiate each other regarding cell proliferation and cortisol production.

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In Vivo and in Vitro Screening for Illegitimate Receptors in Adrenocorticotropin-Independent Macronodular Adrenal Hyperplasia Causing Cushing’s Syndrome: Identification of Two Cases of Gonadotropin/Gastric Inhibitory Polypeptide-Dependent Hypercortisolism

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2004-1256 ◽

2005 ◽

Vol 90 (3) ◽

pp. 1302-1310 ◽

Cited By ~ 61

Author(s):

Jérôme Bertherat ◽

Vincent Contesse ◽

Estelle Louiset ◽

Gaëlle Barrande ◽

Céline Duparc ◽

...

Keyword(s):

Cushing’S Syndrome ◽

Gastric Inhibitory Polypeptide ◽

Cushing's Syndrome ◽

Cortisol Secretion ◽

Adrenal Hyperplasia ◽

Adrenocortical Cells ◽

Normal Cells ◽

H1 Cells

In ACTH-independent macronodular adrenal hyperplasia (AIMAH) causing Cushing’s syndrome, cortisol production can be controlled by illegitimate membrane receptors. The aim of the present study was to evaluate in vivo and in vitro the sensitivity of AIMAH to various regulatory factors to detect the expression of illegitimate receptors by the tissues. Four consecutive patients with AIMAH and hypercortisolism (H1–H4) preoperatively underwent a series of pharmacological and/or physiological tests. After adrenalectomy, in vitro studies were conducted to investigate the cortisol responses of cultured cells, derived from hyperplastic tissues, to various membrane receptor ligands. The adrenal tissues of the two patients who responded in vivo to food intake (H2 and H4) were stimulated in vitro by gastric inhibitory polypeptide. GnRH and human chorionic gonadotropin, but not FSH, stimulated cortisol secretion in patients H2 and H4. In these two cases, human chorionic gonadotropin but not GnRH stimulated cortisol production from cultured adrenocortical cells. Cisapride induced a significant increase in cortisol levels in patient H1. In addition, serotonin (5-HT) was more efficient to stimulate cortisol production in H1 cells than in normal adrenocortical cells. Upright stimulation test provoked an increase in cortisol levels in patients H1, H2, and H3. H1 and H2 cells were more sensitive to the stimulatory action of angiotensin II than normal cells. Similarly, arginine vasopressin (AVP) more efficiently activated steroidogenesis in H1 cells than in normal cells. In H1 tissue, immunohistochemical studies revealed the presence of 5-HT- and AVP-like immunoreactivities within clusters of steroidogenic cells, suggesting that these two factors acted through an autocrine/paracrine mechanism to stimulate cortisol secretion. The present study provides the first demonstration of primary adrenal Cushing’s syndrome dependent on both gonadotropin and gastric inhibitory polypeptide. Our data also show a hyperresponsiveness of hyperplastic adrenal tissues to 5-HT, angiotensin II, and AVP. Finally, they reveal for the first time the presence of paracrine regulatory signals in adrenal hyperplasia tissues.

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