Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

A syndrome of disordered hypothalamic function with abnormal control of temperature, appetite, and thirst, hyperprolactinaemia, and inappropriate vasopressin release is described in a 13-year-old boy who, in addition, had insensitivity to pain and a more general disorder affecting mood, sleep, and control of respiration. A disturbance of the opioid peptide system is postulated. Naloxone reversed central analgesia, altered urine fluid and electrolyte excretion, modified the hormonal response to gonadotrophin-releasing and thyrotrophin-releasing hormones, and improved the auditory and visual reaction times. Specific opioid antagonists may have a therapeutic role.
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PMID:Effect of naloxone in a previously undescribed hypothalamic syndrome. A disorder of the endogenous opioid peptide system? 615 79

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

The effect of hyperprolactinemia on central catecholamine biosynthesis and anterior pituitary hormone release was studied using an in vitro methodology. The incorporation of [3H]tyrosine into hypothalamic and neurohypophyseal catecholamines was determined using a new method which combines high performance liquid chromatography (HPLC) with amperometric detection (LCEC). Elevated plasma prolactin levels, induced by pituitary transplants, resulted in increased in vitro biosynthesis of medial basal hypothalamic (MBH) dopamine (DA), but not norepinephrine (NE). Neurohypophyseal DA biosynthesis (including the intermediate lobe) was not affected. Plasma LH levels were depressed by hyperprolactinemia although the content of hypothalamic luteinizing hormone-releasing hormone (LHRH) was not changed. In parallel studies, the anterior pituitaries from these animals were incubated in vitro using a paired-half technique and LH and PRL release measured. While the basal release of prolactin was not altered by hyperprolactinemia, LH release was significantly decreased. Gonadotroph responsiveness to LHRH was significantly increased, while the inhibition of prolactin by dopamine was not altered. There was a decrease in pituitary prolactin content with normal LH levels. These experiments confirm several in vivo reports which show that hypothalamic dopaminergic but not noradrenergic activity is increased by prolactin. This action is specifically localized in the tuberoinfundibular dopaminergic neurons. Furthermore, these experiments suggest that these central changes result in alterations in both gonadotroph and mammotroph function.
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PMID:Hypothalamic catecholamine biosynthesis and pituitary gonadotropin secretion in vitro: effect of hyperprolactinemia. 634 57

In pathological or experimental hyperprolactinemia, the elevated circulating levels of PRL are the usual cause of the impairment in gonadotropic function. The present study was undertaken to determine whether PRL could suppress basal LH secretion and LHRH-stimulated LH release by a direct action at the anterior pituitary. Anterior pituitaries from ovariectomized rats were incubated in medium 199 alone or in medium 199 containing ovine PRL, and basal and the LHRH-stimulated LH release were followed for 2 or 3 h in vitro. Ovine PRL at 40 and 80 micrograms/ml suppressed basal LH release by 41% and 72%, respectively, at 2 h of incubation. This suppressive effect of both concentrations of PRL continued to the third hour of incubation. LHRH at 5 ng/ml increased the release of LH from pituitaries incubated in medium alone by 57%, 61%, and 107% at 1, 2, and 3 h of incubation, respectively. However, in the pituitaries treated with 40 micrograms/ml ovine PRL, the stimulatory effects of LHRH were diminished at all time points measured. Pretreatment of anterior pituitaries with ovine PRL for 6 h significantly inhibited by 81% the LHRH (5 ng/ml) stimulation of LH release at 2 h of incubation. On the other hand, inhibition of endogenous PRL release by 10(-6) M bromocriptine enhanced the stimulatory effects of 5 ng/ml LHRH by 2.5-fold at 2 h of incubation. The inhibitory effects of PRL on basal and stimulated LH secretion appeared unique, since neither BSA nor vasopressin could elicit similar suppressive effects on LH. These results suggest that in anterior pituitaries exposed to elevated levels of PRL, LH secretion and pituitary responsiveness to LHRH could be impaired. This phenomenon may contribute in part to the antigonadotropic effects of PRL.
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PMID:Prolactin suppresses luteinizing hormone secretion and pituitary responsiveness to luteinizing hormone-releasing hormone by a direct action at the anterior pituitary. 634 62

Eighteen patients aged between 14 and 60 years suffering from diabetes insipidus were studied. Diabetes insipidus was diagnosed by means of Robertson's test. All patients underwent C.T. scanning and evaluation of PRL basally and after TRH (200 mcg e.v.). Twelve patients (66%) showed neurological lesions (secondary central diabetes insipidus). Six of these patients had hyperprolactinaemia. Our data suggest that most of central diabetes insipidus are associated with central system nervous (S.N.C.) damage. In same cases the presence of hyperprolactinaemia suggests a brain damage. Therefore neuroradiological study is very important in all cases of neurohypophyseal diabetes insipidus.
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PMID:[Neurohypophyseal diabetes insipidus. Anatomo-clinical correlations]. 673 10

Prolactin (PRL) has been reported to promote antidiuresis and increase intestinal water-electrolyte absorption, whereas osmolar changes have been shown to influence PRL secretion. However, the mechanisms of action of PRL on the salt-water balance remain unclarified. The present clinical study targeted the effects of hyperprolactinaemia on the secretion of arginine-8-vasopressin (AVP), oxytocin (OXT) and cortisol. Plasma AVP and OXT were measured by radioimmunoassay, and cortisol by fluorimetry. In healthy women (21-39 y, n=6), an oral water load (OWL, 20 ml/bw) significantly suppressed the plasma levels of AVP, OXT and cortisol, and the PRL level too tended to decrease. In hyperprolactinaemic females (22-41 y, n=6, three with pituitary adenomas), water retention was registered following an OWL, together with paradoxical AVP and OXT level increases, whereas the cortisol response remained normal, and the PRL level did not change at all. Histamine (0.5 mg sc) stimulated the release of AVP, OXT and cortisol in the control and hyperprolactinaemic groups alike. These data suggest that alterations in AVP and OXT hypersecretion may contribute to the water retention in hyperprolactinaemia.
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PMID:Neurohypophysial hormone secretion in hyperprolactinaemic women. 984 4

Pituitary adenomas are the most common pituitary disorder affecting pregnancy, and prolactinomas are the most common of the hormone-secreting pituitary adenomas. Hyperprolactinemia must be corrected to allow ovulation and fertility. Bromocriptine has been shown to be safe for use during early gestation. There is less than a 2% risk of microprolactinoma enlargement during pregnancy but a greater than 15% risk of symptomatic enlargement of a macroprolactinoma. Treatment options for patients with macroadenomas include stopping bromocriptine when pregnancy is diagnosed and reinstituting with tumor enlargement, continuous bromocriptine throughout pregnancy, and prepregnancy tumor debulking by surgery. The diagnosis of acromegaly may be difficult to make during pregnancy and relies, in part, on the persistence of the normal pulsatile secretion of growth hormone and loss of this secretory characteristic with a tumor. The growth hormone oversecretion may exacerbate tendencies to gestational diabetes, fluid retention, and hypertension. Treatment for acromegaly and other tumors generally may be deferred until after delivery. There are rare reports of enlargement of clinically nonfunctioning and growth hormone secreting tumors during pregnancy, and surveillance is needed. Tumors may need to be differentiated from lymphocytic hypophysitis. Patients with chronic hypopituitarism usually will need treatment with gonadotropins or pulsatile GnRH to become pregnant and may need increased steroid coverage during labor and delivery. Hypopituitarism developing during pregnancy is usually caused by lymphocytic hypophysitis and usually also will require steroid replacement therapy. Hypopituitarism arising postpartum may be caused by either lymphocytic hypophysitis or Sheehan's syndrome, and the latter may present as an acute or chronic syndrome. Borderline diabetes insipidus may manifest during pregnancy because of increased vasopressin degradation caused by markedly increased levels of placental vasopressinase. Treatment with desmopressin usually is satisfactory. Patients presenting with either anterior or posterior pituitary insufficiency in the peripartum period should always be evaluated for function of the other portion of the pituitary.
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PMID:Pituitary diseases in pregnancy. 988 Jan 16

Virusencephalitis is characterised by clinical symptoms of a parenchymatous inflammation. In addition, early mental status changes often occur as a result of virusencephalitis, beside focal neurological deficiencies, epileptic seizures, cerebral compression, even coma. Other pathological manifestations of virusencephalitis are disturbances of the neurohumoral and the endocrine system, which are often recognised and treated too late. This case report describes symptoms, treatment, and complications of a 76 year old female in-patient, who was diagnosed with virusencephalitis. The number of lymphocytes in the cerebrospinal fluid was increased to 30 cells per microliter, liquor albumin was 1705 mg/l, liquor sugar was 53 mg/dl and liquor lactat was 1.9 mmol/l. IgM antibodies against herpes viruses were found in the cerebrospinal fluid and distinct contrasting foci were found near the mammillary bodies, hypothalamus, tractus opticus, hypophyseal stalk and right parahippocampal in the magnetic resonance imaging of the head, indicating a focal herpes simplex encephalitis. Within seven days, the following symptoms developed: akinetic parkinsonian syndrome, central diabetes insipidus with hypernatremia and polyuria (6 l/die), hypothyreosis, adrenal insufficiency with adynamia, sopor, hypotension and even hypophyseal coma. Panhypopituitarism was diagnosed after measuring the basal hormone levels (ACTH, TSH, FT3, FT4, Cortisol, Prolactin, LH, FSH, ADH) and conducting the pituitary stimulation test. The severeness of all symptoms was slightly improved after substitution with antidiuretic hormone at 0.4 microgram/die and administration of hydrocortisone at 50 mg/die. Administration of amantadine sulphate at 0.6 g/die and L-dopa at 187.5 mg/die for 14 days resulted in a complete regression of the parkinsonism. After administration of aciclovir at 2.25 g/die for 21 days a complete regression of the clinical symptoms could be reached in connection with a decrease of 90% in number and size of cerebral contrasting foci in the magnetic resonance imaging of the head. Three month after therapy, clinical examination and blood serum analysis revealed persistent panhypopituitarism. The present case report is the first description of a viral infection on of the central nervous system (CNS) in combination with parkinsonism, diabetes insipidus, persistent panhypopituitarism and hyperprolactinemia. Early treatment of viral infections of the brain can improve a patient's prognosis dramatically. Early determination and early treatment of a patient's neurohumoral parameters is therefore critical to prevent or reverse early mental status changes like attention disturbances, alterations of personality and behavior, apathy, and slowed cognition.
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PMID:[Virus encephalitis with symptomatic Parkinson syndrome, diabetes insipidus and panhypopituitarism]. 1059 69


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