pituitrin and Adrenal-Hyperplasia--Congenital

Topics: Adrenal Cortex Hormones; Adrenal Gland Diseases; Adrenal Hyperplasia, Congenital; Child; Dwarfism, Pituitary; Endocrine System Diseases; Humans; Metabolism, Inborn Errors; Mixed Function Oxygenases; Pedigree; Pituitary Hormones, Anterior; Thyroid Diseases; Thyroid Hormones; Vasopressins

Cortisol secretion in adrenal Cushing's syndrome can be regulated by the aberrant adrenal expression of receptors for gastric inhibitory polypeptide, vasopressin, catecholamines, LH/human CG (LH/hCG), or serotonin. Four patients with incidentally discovered bilateral macronodular adrenal hyperplasia without clinical Cushing's syndrome were evaluated for the possible presence of aberrant adrenocortical hormone receptors. Urinary free cortisol levels were within normal limits, but plasma cortisol levels were slightly elevated at nighttime and suppressed incompletely after dexamethasone administration. Plasma ACTH was partially suppressed basally but increased after administration of ovine CRH. A 51-yr-old woman had ACTH-independent increases of plasma cortisol after 10 IU AVP im (292%), 100 microg GnRH iv (184%), or 10 mg cisapride orally (310%); cortisol also increased after administration of NaCl (3%), hCG, human LH, and metoclopramide. In a 61-yr-old man, cortisol was increased by AVP (349%), GnRH (155%), hCG (252%), and metoclopramide (191%). Another 53-yr-old male increased plasma cortisol after AVP (171%) and cisapride (142%). Cortisol secretion was also stimulated by vasopressin in a 54-yr-old female. This study demonstrates that subclinical secretion of cortisol can be regulated via the aberrant function of at least V1-vasopressin, LH/hCG, or 5-HT4 receptors in incidentally identified bilateral macronodular adrenal hyperplasia.

Topics: Adrenal Hyperplasia, Congenital; Cisapride; Cushing Syndrome; Dopamine Antagonists; Female; Follicle Stimulating Hormone; Gonadotropin-Releasing Hormone; Hormones; Humans; Hydrocortisone; Male; Membranes; Metoclopramide; Middle Aged; Receptors, Cell Surface; Vasopressins

Bilateral macronodular adrenal hyperplasia (BMAH) is a rare cause of Cushing's syndrome (CS) and its familial clustering has been described previously. Recent studies identified that ARMC5 mutations occur frequently in BMAH, but the relation between ARMC5 mutation and the expression of aberrant G-protein-coupled receptor has not been examined in detail yet.. We studied a large French-Canadian family with BMAH and sub-clinical or overt CS. Screening was performed using the 1-mg dexamethasone suppression test (DST) in 28 family members. Screening for aberrant regulation of cortisol by various hormone receptors were examined in vivo in nine individuals. Sequencing of the coding regions of ARMC5 gene was carried out.. Morning ambulating cortisol post 1 mg DST were >50 nmol/l in 5/8 members in generation II (57-68 years old), 9/22 in generation III (26-46 years old). Adrenal size was enlarged at different degrees. All affected patients increased cortisol following upright posture, insulin-induced hypoglycemia and/or isoproterenol infusion. β-blockers led to the reduction of cortisol secretion in all patients with the exception of two who had adrenalectomies because of β-blockers intolerance. We identified a heterozygous germline variant in the ARMC5 gene c.327_328insC, (p.Ala110Argfs*9) in nine individuals with clinical or subclinical CS, in four out of six individuals with abnormal suppression to dexamethasone at initial investigation and one out of six individuals with current normal clinical screening tests.. Systematic screening of members of the same family with hereditary BMAH allows the diagnosis of unsuspected subclinical CS associated with early BMAH. The relation between the causative ARMC5 mutation and the reproducible pattern of aberrant β-adrenergic and V1-vasopressin receptors identified in this family remains to be elucidated.

Topics: Adrenal Glands; Adrenal Hyperplasia, Congenital; Adrenalectomy; Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Adult; Aged; Armadillo Domain Proteins; Cushing Syndrome; Dexamethasone; Germ-Line Mutation; Humans; Hydrocortisone; Insulin; Isoproterenol; Middle Aged; Pedigree; Posture; Propranolol; Quebec; Receptors, Adrenergic, beta; Receptors, Vasopressin; Tomography, X-Ray Computed; Tumor Suppressor Proteins; Vasopressins

A 78-year-old woman diagnosed with non-classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency had been under glucocorticoid replacement therapy since the age of 17 years. After several weeks of suffering from gastroenteritis with vomiting, she presented with disturbance of consciousness, hypotension, dehydration, and severe hyponatremia (108 mEq/L) and a markedly increased serum vasopressin concentration (45.5 pg/mL). She regained consciousness after correcting her body-fluid balance with hypertonic saline and intravenous hydrocortisone sodium therapy. Her hyponatremia was likely caused by extra-renal sodium loss and impaired water excretion induced by an increase of serum vasopressin due to volume depletion and glucocorticoid deficiency.

Topics: Adrenal Hyperplasia, Congenital; Adrenal Insufficiency; Aged; Female; Glucocorticoids; Humans; Hyponatremia; Saline Solution, Hypertonic; Sodium; Vasopressins

Cushing's syndrome due to familial ACTH-independent macronodular adrenal hyperplasia (AIMAH) has been reported in small kindreds. In vasopressin-sensitive AIMAH (VPs-AIMAH), VP stimulates an aberrant, ACTH-independent increase in cortisol. The aims of this study were to (i) delineate the preclinical phenotype of VPs-AIMAH in a three-generation kindred (AIMAH-01) and two smaller kindreds (AIMAH-02 and AIMAH-03) and (ii) investigate the aetiology of VP sensitivity in AIMAH-01.. Clinical studies of three kindreds for adrenal tumours or early Cushing's and molecular studies of adrenal tumours (AIMAH-01).. Thirty-three individuals, from three kindreds, were screened for perturbations of the hypothalamic-pituitary-adrenal axis or adrenal tumours.. Patients underwent clinical, biochemical and adrenal imaging investigations. Evaluation included low-dose (1 IU/70 kg) VP stimulation. Adrenal VP receptor (AVPR1A, AVPR1B, AVPR2) expression (AIMAH-01) was assessed using RT-PCR and immunohistochemistry (IHC). IHC for VP was also performed.. AIMAH-01 had three siblings with Cushing's, and four individuals with suppressed ACTH/aberrant VP responses and/or adrenal nodules. In AIMAH-02, a father and son were affected. AIMAH-03 had three siblings with Cushing's. RT-PCR showed adrenal overexpression of AVPR1A and AVPR1B. IHC detected AVPR1A. The adrenal tumour from one patient also stained weakly for VP and AVPR2.. Adrenal nodules, suppressed ACTH and increased VP sensitivity may represent preclinical disease, allowing early detection, and treatment, of affected individuals. In AIMAH-01, increased VP sensitivity may be due to adrenal VP receptor overexpression. In these kindreds, VPs-AIMAH is familial, and autosomal dominant inheritance is most likely.

Topics: Adrenal Gland Neoplasms; Adrenal Hyperplasia, Congenital; Adrenocorticotropic Hormone; Adult; Aged; Cushing Syndrome; Female; Gene Expression; Humans; Male; Middle Aged; Pedigree; Receptors, Vasopressin; Vasopressins; Young Adult

A major difficulty in the clinical management of congenital adrenal hyperplasia (CAH) is adjustment of glucocorticoid doses to suppress ACTH and androgens without causing iatrogenic hypercortisolism. The possibility that structural alterations of the adrenal or a dysfunction of the hypothalamic pituitary adrenal (HPA) axis caused by glucocorticoid deficiency during fetal life contribute to this problem was studied in 21-hydroxylase deficient mice caused by deletion of the cytochrome P-450 21-hydroxylase gene. Homozygotes showed about 200-fold elevations in plasma progesterone, hyperplastic adrenal cortices lacking zonation, and structural alterations of adrenocortical mitochondria. Histochemical studies showed increases in hypothalamic CRH messenger RNA (mRNA) and immunoreactive (ir) CRH, and pituitary POMC mRNA in homozygous mice. VP mRNA levels in PVN perikarya were normal, but irVP in parvicellular terminals of the median eminence was increased in homozygotes. Prenatal dexamethasone treatment (0.5 to 2 microg/day) prevented the increases in CRH mRNA, whereas dexamethasone only partially decreased POMC mRNA levels, and had no effect on serum progesterone levels. The data suggest that intrauterine glucocorticoid deficiency in CAH causes hyperactivity of the hypothalamic-pituitary-corticotroph axis and insensitivity to glucocorticoid feedback. These studies in 21-hydroxylase deficient mice may provide new insights on the mechanism, clinical manifestations and management of some types of human CAH.

Topics: Adrenal Glands; Adrenal Hyperplasia, Congenital; Animals; Animals, Newborn; Corticotropin-Releasing Hormone; Dexamethasone; Fetus; Glucocorticoids; Hypothalamo-Hypophyseal System; Hypothalamus; Mice; Mice, Inbred C57BL; Pituitary Gland; Pituitary-Adrenal System; Pro-Opiomelanocortin; Progesterone; Vasopressins