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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied neurohypophyseal function in 12 women with postpartum hypopituitarism (Sheehan's syndrome) by measuring plasma arginine vasopressin concentrations during 5% hypertonic saline infusions. All patients had a history of obstetric shock or massive bleeding, and were receiving cortisol and/or L-T4 replacement therapy. None had any symptoms of diabetes insipidus. The mean basal plasma vasopressin level in the patients [0.6 +/- 0.1 (+/- SE) pmol/L] was significantly lower (P less than 0.01) than that in normal adults (2.5 +/- 0.5 pmol/L; n = 12), whereas mean plasma osmolality values were similar in the two groups. During hypertonic saline infusion, the 10 hypopituitary patients had varying degrees of subnormal arginine vasopressin responses to the increase in plasma osmolality. Urine-concentrating ability after dehydration also was lower in the patients, although overt polyuria was absent at the time of this study. These results indicate that the osmoregulation of arginine vasopressin secretion is frequently impaired in postpartum hypopituitarism, suggesting neurohypophyseal damage.
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PMID:Neurohypophyseal function in postpartum hypopituitarism: impaired plasma vasopressin response to osmotic stimuli. 291 58

A 22-year old woman in the 37th week of her third pregnancy (twins) developed acute fatty liver complicated with a haemorrhagic syndrome from disseminated intravascular coagulation. Two normal girls were delivered by caesarean section. Persistent surgical bleeding required hysterectomy and a short stay in an intensive care unit. The disseminated intravascular coagulation subsided within 8 days. Three weeks after delivery a pituitary insufficiency (Sheehan's syndrome) was diagnosed. A second liver biopsy showed that the lesions had regressed. One week after delivery, the patient developed polyuria and polydipsia. The diagnosis of diabetes insipidus was confirmed by the lack of increase of plasma antidiuretic hormone level during an 8-hour water deprivation test. The pathophysiology of these different syndromes is discussed. Disseminated intravascular coagulation might be the link between hypopituitarism and diabetes insipidus.
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PMID:[Twin pregnancy with acute hepatic steatosis followed by antehypophyseal insufficiency and diabetes insipidus]. 316 Oct 48

A case of a 69-year-old woman with postpartum hypopituitarism (Sheehan's syndrome) associated with congestive heart failure and severe hyponatremia is reported. She developed congestive heart failure after cholecystectomy, and marked improvement was noted by treatment with oxygen, digoxin, furosemide, and dopamine. Two weeks after surgery, she became confused, and hyponatremia, 106 mEq/l, was detected. She was referred to us. Past history revealed postpartum hemorrhage at the age of 34, followed by a failure to lactate, menoschesis, and loss of pubic hair and axillary hair. Hypertonic saline (1.5%) infusion and water restriction increased her serum sodium concentration into the low normal range. Despite hyponatremia, serum vasopressin was not suppressed. Basal levels of pituitary hormones were low, and they did not respond to provocation tests. Marked impairment of water excretion was noted, and plasma vasopressin was not suppressed during a water-loading test. These results suggest that inappropriately increased vasopressin played an important role in impaired water excretion, and this defect could have been responsible for the development of hyponatremia and congestive heart failure in this patient.
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PMID:A case of postpartum hypopituitarism (Sheehan's syndrome) associated with severe hyponatremia and congestive heart failure. 326 36

Nine cases with hyponatremia were precisely examined during the past 2 years. Seven of them showed normal plasma volume, serum aldosterone and pituitary function, although ADH was detected. Therefore, those seven cases were diagnosed without dilutional hyponatremia due to SIADH (a syndrome of inappropriate secretion of antidiuretic hormone). The mechanism of hyponatremia of such a type has not been yet explained definitely, but it may be referring to excess natriuresis. Only each one case of hyponatremia due to hypopituitarism and dilutional hyponatremia due to SIADH was verified in this series. SIADH showing high plasma volume value was thought to be rare. Differential diagnosis between SIADH and hyponatremia due to excess natriuresis is essential and simple. Non-invasive plasma volume measurement using RISA is significantly useful for it. For the hyponatremia due to excess natriuresis, water restriction is not necessary, but digestive supply of NaCl is needed.
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PMID:[Hyponatremia due to excess natriuresis]. 341 57

Two adult patients with unilateral hypoplastic optic nerves, absent septa pellucida and hypopituitarism are described. Patient 1, aged 20, presented with diabetes insipidus due to partial vasopressin deficiency. Patients 2, aged 29, presented with focal epilepsy. Both had short stature. They showed absent growth hormone (GH) response to insulin-hypoglycaemia or glucagon, but responded to 100 micrograms growth hormone releasing factor (GRF-44) with a rise in circulating GH, suggesting a hypothalamic defect in GH release though a co-existing pituitary defect cannot be excluded. Other hypothalamic-pituitary functions were normal. These two patients probably represent the milder form of the clinical spectrum of septo-optic dysplasia which, with the extensive use of CT brain scans, will be increasingly encountered by physicians attending adult patients.
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PMID:Hypothalamic defects in two adult patients with septo-optic dysplasia. 375 51

To evaluate the role of antidiuretic hormone (ADH) in the defect in water excretion which is characteristic of glucocorticoid deficiency, the effects of hydrocortisone and ethanol upon urinary dilution during a sustained water load were studied in patients with anterior hypopituitarism. A spectrum of defects in urinary dilution was found in the seven patients with anterior hypopituitarism, and the subjects were separable into two groups. Four patients were unable to excrete a urine hypotonic to plasma (group I) while three diluted the urine (group II). In two of the group II patients, despite maintenance of hydration, urinary osmolality later rose to hypertonicity. Physiological doses of hydrocortisone improved urinary dilution in all patients. Submaximal doses of oral hydrocortisone, when given to the group I patients, converted their response to hydration to one characteristic of the group II patients, i.e., an initial hypotonic urine followed by a secondary rise to hypertonicity. Ethanol, a known inhibitor of ADH secretion, had no effect in the group I patients. When two of these patients were pretreated with sub-maximal doses of hydrocortisone, however, so that they were able to transiently dilute the urine, ethanol prevented the secondary rise in urine osmolality. Similarly, the administration of ethanol to the untreated group II patients, when the urine was hypotonic, improved diluting ability as characterized by a lowering of urinary osmolality and an increased excretion of solute-free water in all three patients. Hydrocortisone did not improve urinary dilution in three patients with complete hypophyseal diabetes insipidus and one with both anterior and posterior insufficiency receiving constant infusions of vasopressin. These data suggest, therefore, that inappropriately elevated levels of ADH play a major role in the defect in water excretion of anterior hypopituitarism. Glucocorticoids appear to be necessary for a normal neurohypophyseal response to inhibitory stimuli.
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PMID:Role of antidiuretic hormone in the abnormal water diuresis of anterior hypopituitarism in man. 509 63

The first half of this manuscript is devoted to a review of the methods used and the results obtained in the published measurements of the normal responses to tests of the three main types of hypothalamic-pituitary-adrenocortical (HPA) activity in man. These are, I, basal, unstressed activity leading to appropriate levels of total daily production of cortisol in the characteristic circadian pattern; II, responses to feedback stimulation of HPA activity by metyrapone administration; and III, responses to tests of the effects of stress on the HPA system including the effects of hypoglycemia, induced fever, vasopressin administration, and ACTH injections and infusions. The advantages and shortcomings of each type of procedure are discussed. The second half of this paper describes the authors' attempts to establish the limits of normality of standard and modified methods of evaluating the HPA system. The defined limits of normality have been used to assess the HPA function in 158 patients with known or suspected disorders of the HPA system. In normal controls, halfhourly plasma cortisol determinations established the normality of circadian and postprandial fluctuations and of mean plasma cortisol concentration, 6.2 +/- 0.3 (SEM) micrograms/dl, which were closely approximated by determinations every 6 h. Metyrapone, given in a dose of 500 mg every 2 h for 24 h increased urinary 17-OHCS excretion to 10.5-32.6 mg/day or to 1.7-7.8 times basal excretion rate. Increasing rates of insulin infusion disclosed significant relationships between resulting plasma glucose and cortisol concentrations. The slopes of the delta cortisol/delta glucose responses were similar after insulin infusions (0.46 +/- 0.05) and after insulin injections, 0.15 U/kg (0.43 +/- 0.09), and were always greater than 0.20 micrograms/mg. This index provides a useful objective measure of the normality of responses to hypoglycemic stress, 0.20-0.87 micrograms/mg. Adrenocortical responses to iv infusions of ACTH (cosyntropin 0.25 mg) may be equivocal at 2 h but are clear cut at 4, 6 and 8 h. Of 158 patients in whom hypopituitarism was known or suspected because of the presence of a pituitary tumor, acromegaly, hyperprolactinemia, or clinical features, HPA function was found to be entirely normal in 88 patients and partially or severely abnormal in the remaining 70 patients.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Normal and abnormal function of the hypothalamic-pituitary-adrenocortical system in man. 608 18

In a 20-year-old woman, a complicated full-term delivery was followed by a 14-month history of galactorrhea, amenorrhea, and symptoms of hypocortisolism. Evaluation revealed the presence of an empty sella, hyperprolactinemia, and an isolated pituitary deficiency of ACTH, resulting in secondary adrenal insufficiency. The defect in ACTH secretion was apparently due to intrinsic pituitary rather than hypothalamic disease, because administration of lysine vasopressin did not stimulate ACTH release. An empty sella with hyperprolactinemia has been described before. However, to the authors' knowledge, isolated ACTH deficiency as a complication of postpartum hypopituitarism (atypical Sheehan's syndrome) in association with an empty sella and hyperprolactinemia has not previously been reported.
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PMID:Primary empty sella, hyperprolactinemia, and isolated ACTH deficiency after postpartum hemorrhage. 630 Dec 77

It can be readily appreciated from the preceding discussion that many endocrine and non-endocrine tests are available for the evaluation of patients with suspected hypothalamic-pituitary disease. The endocrine evaluation of these subjects should be tailored according to the type and extent of pathology suspected (see Tables 2 and 3). For patients with pituitary adenomas and clinical features of hyperpituitarism, such as hyperprolactinaemia, Cushing's disease or acromegaly, the initial tests should be directed at the hormone whose excess is suspected. For example, a glucose suppression test for acromegaly or dexamethasone suppression test for Cushing's disease should be performed early in the evaluation. The possibility of deficiencies of the other pituitary hormones should then be addressed in patients with secretory tumours, but initially in those with apparent non-functioning adenomas. In patients with large macroadenomas pituitary hormone deficiencies are almost invariable with GH and FSH/LH being the most commonly affected, followed by TSH and ACTH in that order (Snyder et al, 1979a; Valenta et al, 1982). Basal thyroid function tests, serum oestradiol or testosterone, and basal gonodotrophins should be routinely obtained in patients with macroadenomas. Additionally, the integrity of the pituitary-adrenal axis should be determined and an overnight water deprivation test for assessment of neurohypophyseal function is also recommended. GH stimulation testing is valuable as a test of pituitary function in patients with suspected pituitary tumours since GH reserve is lost very early in the development of hypopituitarism. Evaluation of the pituitary-thyroid axis with TRH or the pituitary gonadal axis with LHRH generally provides limited additional information of diagnostic value in individual patients with macroadenomas. However, the 'paradoxical' responses to TRH and LHRH may be useful as a biological marker following therapy in patients with GH- or ACTH-secreting tumours. In patients with microadenomas, pituitary hormone deficiencies are uncommon (Valenta et al, 1982). Despite this observation, it may be beneficial to determine basal thyroid levels, gonadotrophin levels, serum testosterone or oestradiol levels, and the response to an overnight metyrapone test in such patients to provide a baseline for future care.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Investigation of hypothalamic-pituitary disease. 632 63

Twenty patients with postpartum hypopituitarism underwent a dehydration test followed by the administration of synthetic arginine-vasopressin (DDAVP; desmopressin). Panhypopituitarism was confirmed by hormonal assays in the basal state and after stimulation with combined luteinising hormone releasing hormone-thyrotrophin releasing hormone-insulin. All the patients were given replacement therapy with hydrocortisone and thyroid hormones. Results were compared with those in 12 normal women. Urinary concentrating ability was diminished in the patients as compared with the controls (maximum urine osmolality 688 (SEM 23) mmol (mosmol)/kg in the patients v 967 (SEM 29) mmol/kg in the controls). Also the change in urine osmolality after administration of desmopressin was greater in the patients (+9.55 (SEM 1.98)% in the patients v 2.49 (SEM 0.96)% in the controls). Partial diabetes insipidus is apparently common in Sheehan's syndrome. This association should be borne in mind when managing these patients, especially those in acute failure.
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PMID:Antidiuretic function in Sheehan's syndrome. 643 99


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