Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

Plasma ACTH (normal value: 0.16 plus or minus mU/100 ml) was measured in 116 patients with Cushing's syndrome, using a bioassay including dynamic tests and sequential determinations. In 10 patients with adrenal tumors ACTH levels were nondetectable (ND) or low, and usually nonstimulatable. In 10 patients with ectopic ACTH secretion high levels (0.42 plus or minus 0.07 mU/100 ml) were measured. The extracts of 6 tumors yielded an ACTH-like substance. Forty-three patients with Cushing's disease (without pituitary tumor) had, before treatment, a mean ACTH level of 0.18 plus or minus 0.01 mU/100 ml, accompanied by high levels of plasma cortisol (32.1 plus or minus 1.9 mug/100 ml). Irregular nycthemeral variations occurred. ACTH rose to 0.30 mU/100 ml after incomplete adrenalectomy (20 patients) and to 1.14 mU/100 ml after total adrenalectomy (21 patients). Dexamethasone (8 mg per day) suppressed ACTH levels. Metyrapone induced a normal ACTH rise, but at abnormal times. Lysine-vasopressin (LVP) induced an ACTH mean relative increase of 120% before, and of 140% after adrenalectomy (i.e., within the normal range). Six nonadrenalectomized patients with pituitary tumors showed similar abnormalities of ACTH regulation. However, the ACTH rise after LVP was above 500%. When pituitary tumors occurred after adrenalectomy (12 patients) the mean basal ACTH level was 18 mU/100 ml. Dexamethasone induced a 90% decrease, and LVP a 416% increase in ACTH levels. In 6 patients with nodular adrenal hyperplasia, ACTH was undetectable before treatment. After adrenalectomy, ACTH rose to 0.4 mU/100 ml (11 patients) and the increase after LVP was 90%. Five additional patients developed pituitary tumors. These data confirm the abnormalities of ACTH feedback regulation in Cushing's disease. However, even when pituitary tumors occur, ACTH levels can be altered by metyrapone, dexamethasone and LVP. This last test is of particular interest for the detection of pituitary tumors. The follow-up pattern of treated nodular adrenal hyperplasia appears to be very similar to that of Cushing's disease.
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PMID:Studies of ACTH secretion control in 116 cases of Cushing's syndrome. 16 70

Hypothalamic extract stimulates the release of corticotropin (ACTH) and endorphins 2.5- to 30-fold in mouse pituitary tumor cell cultures (AtT-20/D(16v) line) and primary cell cultures from mouse anterior pituitary. ACTH and endorphin activities were measured by radioimmunoassay and immunoprecipitation. Pretreatment of tumor cell cultures with 1 muM dexamethasone reduced the stimulatory effect of the extract on release of ACTH and endorphins. Pretreatment of primary cell cultures with 10(-6) M dexamethasone reduced the stimulatory effect of both vasopressin and the extract on the release of ACTH and endorphins. Release of ACTH and endorphin was coupled in both kinds of cultures in the basal, stimulated, and inhibited states. The molecular weight forms of ACTH and endorphin in tumor cell culture medium were analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Radioimmunoassay and immunoprecipitation show that the 13,000-dalton and 4500-dalton forms of ACTH were present in about equal amounts in medium from cultures incubated with or without hypothalamic extract for 15 min, 30 min, or 2 hr. Smaller amounts of the high molecular weight forms of ACTH (20,000- to 23,000-dalton and 31,000-dalton ACTH) were observed in the culture medium at these times. The predominant forms of endorphin released after 20 min or 3 hr of incubation had molecular weights of 31,000, 11,700 (beta-lipotropic hormone-size material) and 3500 (beta-endorphin-size material). No degradation of the forms of endorphin released into the culture medium was observed after incubating the culture medium for 1.5 hr in the absence of cells. The proportions of the different forms of endorphin and ACTH present in the culture medium resembles that seen in cell extracts.
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PMID:Coordinate control of corticotropin, beta-lipotropin, and beta-endorphin release in mouse pituitary cell cultures. 21 8

The term Cushing's disease is applied to those cases of Cushing's syndrome in which hypercortisolism is secondary to inappropriate secretion of ACTH by the pituitary. Studies on control of ACTH secretion in these patients reveal: (a) that the episodic secretion of ACTH is similar to the normal; however, frequency and amplitude of the secretory episodes lack the normal circadian rhythm; (b) that ACTH release can be stimulated by vasopressin and metyrapone in a normal or above-normal manner; and (c) that it can be suppressed by large doses of corticosteroids. When the dynamic aspects of the ACTH response to corticosteroid administration are studied, it appears that the normally negative differential feedback mechanism is converted into a positive one, whereas the delayed, integral mechanism is undisturbed. Patients with Cushing's disease in the presence of obvious pituitary tumors cannot be distinguished from those without pituitary tumors by studying only the pituitary function. All these and other well-known facts would favor the concept that ACTH secretion in Cushing's disease is under hypothalamic control whether or not a pituitary tumor is present. Moreover, there are observations that suggest that brain centers superior to the hypophysiotropic area of the hypothalamus are involved in the pathophysiology of Cushing's disease. This concept has led to the discovery of neurotropic drugs that are able to induce complete remission of Cushing's syndrome in a cerain percentage of patients. In some patients with severe psychiatric diseases, neuroendocrine abnormalities are present that resemble closely those characteristic for Cushing's disease. With the most refined neuroradiological methods, pituitary microadenomas are demonstrable in approximately 70% of patients with Cushing's disease, and this number compares well with those of earlier autopsy findings (70 to 80%). In a small number of patients (4 to 10%), these tumors are large and can easily be detected by standard roentgenograms of the head. Recent studies on the frequency of these large tumors do not support the hypothesis that adrenalectomy accelerates the progression of these tumors. In this case the term "Nelson's syndrome" would be uncessary. It is established that complete cure of Cushing's disease can be obtained in most patients with selective removal of a microadenoma from the pituitary gland. The current experience with this microsurgical procedure caused a renewed interest in Cushing's original suggestion that the disease is primarily a pituitary disorder. However, there are already a number of enigmatic observations. Possibly, the recent ultrastructural studies using immunocytochemical methods will resolve some of these problems. At this moment it is impossible to decide whether Cushing's disease is primarily a CNS or a pituitary disorder, when all arguments for one or the other hypothesis are taken into account...
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PMID:Pathophysiology of Cushing's disease. 22 10

A case of a 21-year-old woman with Cushing's disease due to a pituitary tumor is described. The patient was treated with cyprohepatadine for 4 weeks immediately following pituitary alpha-particle irradiation. A standard vasopressin test to measure ACTH-mediated cortisol release was performed four times: prior to pituitary irradiation, after irradiation, after 4 weeks of cyproheptadine therapy, and off cyproheptadine for 2 weeks. Cyproheptadine failed to modify vasopressin-stimulated cortisol release in the patient described. This study suggests that cyproheptadine, which has previously been shown to decrease ACTH secretion, probably acts principally at the hypothalamic, rather than at the pituitary level.
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PMID:Failure of cyprohepatdine to inhibit vasopressin-stimulated cortisol release in a patient with Cushing's disease. 101 93

The presence of 3 different neuropeptide mRNAs with a strict cell-specific expression in vivo was investigated in 13 tumor cell lines from neuroendocrine and in 23 tumor cell lines from non-neuroendocrine origin. Northern blots showed no expression of mRNA for vasopressin (VP) in the 36 tested cell lines. Very low oxytocin (OT) mRNA hybridization signals were detected in the rat pituitary tumor cell line GH4C2 and the rat pancreas tumor cell line RIN5. Both the rat pituitary tumor cell line AtT-20 and the human myeloid leukemia cell line K562, contained proopiomelanocortin (POMC) mRNA. The low incidence of VP, OT and POMC gene expression in the tested tumor cell lines was not influenced by treatments inducing differentiation. In contrast, the cholecystokinin (CCK) gene which is widely present in nervous and endocrine systems was abundantly expressed in the human primitive neuroepithelioma cell line SK-N-MC and its clonal derivative SK-N-MC-IX-C. The results indicate that the expression of neuropeptide genes is very rare in tumor cell lines. The lack of expression in undifferentiated cells agrees with the appearance of expression after day 13 of the embryogenesis when maturation of neurons begins.
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PMID:Survey of neuropeptide gene expression in tumor cell lines. 132 Aug 92

A 53-yr-old man with Cushing's disease was found to have a pituitary carcinoma with metastases to the liver and lung which produced both CRH and ACTH simultaneously. Despite removal of the pituitary tumor, his Cushing's disease worsened. Endocrinological examination then demonstrated elevated plasma CRH and markedly elevated plasma ACTH, beta-lipotropin, and cortisol concentrations, increased urinary 17-hydroxycorticosteroid and 17-ketosteroid excretion, and no suppression of serum cortisol after low or high dose dexamethasone administration. Urinary 17-hydroxycorticosteroid excretion increased in response to metyrapone, and lysine vasopressin elicited a striking increase in plasma ACTH. A computed tomographic scan of abdomen revealed multiple hypodense areas in the liver and bilateral adrenal hyperplasia. Postmortem histological examination revealed a necrotic hemorrhagic pituitary carcinoma with metastases to the liver, lung, and olfactory bulb. Immunohistochemical staining, gel filtration, and Northern blot analysis of liver and lung metastases revealed evidence of the production of both CRH and ACTH in these metastases. We concluded that the patient's pituitary carcinoma produced both CRH and ACTH.
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PMID:Corticotropin-releasing hormone- and adrenocorticotropin-producing pituitary carcinoma with metastases to the liver and lung in a patient with Cushing's disease. 169 98

The effects of cortisol, its steric analog 11-epicortisol, and lysine vasopressin (LVP) on DNA and RNA synthesis in isolated adrenocorticotropic hormone-secreting human pituitary tumor cells obtained by transsphenoidal surgery were studied using [3H]thymidine incorporation in DNA and [3H]uridine in RNA. Cortisol suppressed RNA and, to a greater extent, DNA synthesis in these cells. This could explain the slow growth of pituitary tumors in patients with Cushing's disease and the rapid growth of Nelson's pituitary tumors after bilateral adrenalectomy. 11-Epicortisol also suppressed RNA synthesis, but it had a stimulatory effect on DNA synthesis, which indicates a high specificity of glucocorticoid receptors. When applied together with cortisol, 11-epicortisol antagonized the suppressive effects of cortisol on DNA synthesis. Although LVP stimulated RNA synthesis, it suppressed DNA synthesis in most of the tumor cells.
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PMID:The effects of cortisol, 11-epicortisol, and lysine vasopressin on DNA and RNA synthesis in isolated human adrenocorticotropic hormone-secreting pituitary tumor cells. 215 95

Interleukin 1 (IL-1) has been shown to potentiate the release of beta-endorphin induced by secretagogues, including corticotropin releasing factor (CRF) and phorbol ester (TPA), in the mouse AtT-20 pituitary tumor cell line (Fagarasan et al., PNAS, 1989, 86, 2070-2073). In cultured rat anterior pituitary cells, pretreatment with IL-1 caused only a small increase in beta-endorphin release but significantly potentiated CRF-and vasopressin-stimulated beta-endorphin secretion. Vasopressin stimulates the secretion of beta-endorphin in normal pituitary cells but not in AtT-20 cells. However, treatment of AtT-20 cells with IL-1 induced the expression of vasopressin-mediated beta-endorphin release; this effect of IL-1 was reduced after depletion of protein kinase C by prolonged treatment with TPA. The enhancement of CRF-stimulated beta-endorphin release by IL-1 was also reduced in AtT-20 cells after depletion of protein kinase C, and after treatment with staurosporine. These findings indicate that treatment with IL-1 amplifies receptor-mediated responses to the major physiological secretagogues in normal corticotrophs, and initiates a secretory response to vasopressin in AtT-20 cells.
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PMID:Interleukin 1 potentiates agonist-induced secretion of beta-endorphin in anterior pituitary cells. 226 59

In order to investigate the production and secretion of hypothalamic factors by the prolactin and proopiomelanocortin (POMC)-derived, peptide-producing, transplantable rat pituitary tumor 7315a, we determined the concentrations of corticotropin-releasing factor (CRF)- and vasopressin (AVP)-like immunoreactivities (IR) in the tumor extracts [14.0 +/- 1.6 (SE) and 4.2 +/- 0.9 pmol/g, respectively] and incubation media (0.26 +/- 0.01 and 0.07 +/- 0.01 pmol/10(7) cells/h, respectively). Total peptide content correlated well with tumor weight. Moreover, there is a very good correlation between the CRF and AVP IR, but not as good between CRF or AVP IR and POMC peptide IR tumor contents. Tumor extracts were chromatographed on Sephadex G-75 and compared with chromatograms of stalk median eminence (SME) extracts from normal Buffalo rats. CRF IR in tumor chromatograms gave an unusual pattern of peaks. About 31% of the total CRF IR was eluted in the high molecular weight region. The major portion of CRF IR was located in a wide region of lower molecular weight. The AVP radioimmunoassay revealed a similar pattern of peaks in tumor and SME chromatograms. A propressophysin-like peak and a smaller peak coeluting with synthetic AVP were detected. Immunohistochemical staining of consecutive sections of the tumor indicated that AVP and CRF are often found in the same cell, but the CRF and AVP-producing cells are clearly distinct from the POMC peptide-producing cells.
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PMID:Corticotropin-releasing factor and vasopressin production in the rat pituitary tumor 7315a: biochemical and immunohistochemical studies. 254 Sep 7

A 71-year-old man was referred to Tokai University Hospital because of cold intolerance, slow speech and slowing down of his intellectual and motor activities. Free thyroxine index, and free T-4 and T-3 levels were low (1.4, 0.7 ng/dl and 0.4 ng/ml, respectively) with normal TSH (2.5 microIU/ml). A skull X-ray showed enlargement of the sella turcica and his CT scan revealed an intrasellar mass. LH, FSH, ACTH and PRL did not rise in response to the intravenous administration of LH-RH and insulin. A diagnosis of pan-hypopituitarism due to a pituitary tumor was established. The release of ACTH and cortisol was restored under stimulation of CRF or lysine vasopressin. TSH responded to TRH in a delayed manner. The pituitary tumor was removed by a transsphenoidal operation and diagnosed histologically as craniopharyngioma. Our hospital has experienced nine cases of craniopharyngioma in the last 10 years but the present case was the only intrasellar craniopharyngioma.
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PMID:A case of intrasellar craniopharyngioma. 283 33


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