Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tissues from 12 human corticotropin-secreting adenomas, obtained during transsphenoidal surgery for Cushing's disease (CD, ten cases) or Nelson's syndrome (NS, two cases), were mechanically dispersed. The resulting single cells and cell aggregates were plated on extracellular matrix derived from bovine corneal endothelia. CD and NS cells showed distinct morphological differences initially, CD cells being much more spherical than the flattened NS cells. By 10 days at the latest after plating, however, CD and NS cells were indistinguishable morphologically. Cultured cells from both entities responded with rounding to cortisol (hydrocortisone, 10(-6) M) within 4-6 h. Synthetic ovine corticotropin-releasing factor (10(-8) M) produced flattening and extension of cytoplasmic processes after as early as 2 h.
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PMID:Long-term culture of human corticotropin-secreting adenomas on extracellular matrix and evaluation of serum-free conditions. Morphological aspects. 302 32

Pituitary carcinoma is defined as a malignant pituitary tumour associated with blood- or lymph-borne metastases. Cushing's disease is frequently present in patients with this condition. After adrenalectomy for Cushing's disease, a 37-year-old man developed Nelson's syndrome resulting from a pituitary carcinoma with metastases to the spinal cord, cauda equina, heart, liver, and pancreas. The primary tumour and its metastases showed immunocytochemical staining for ACTH, beta-lipotrophin, and variably for beta-endorphin and alpha-melanocyte stimulating hormone (alpha-MSH). A coincidental glioblastoma was also present. Nine cases of Cushing's disease associated with pituitary carcinoma, including the present patient, are documented in the literature. The case reported is only the second in which immunohistochemical staining of the primary pituitary tumour and its metastases was performed, and the first in which ACTH-related peptides, in addition to ACTH itself, were demonstrated in the carcinoma cells.
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PMID:Pituitary pro-opiomelanocortin-cell carcinoma occurring in conjunction with a glioblastoma in a patient with Cushing's disease and subsequent Nelson's syndrome. 302 76

Sixty-one pituitary corticotroph adenomas from 47 patients with Cushing's disease, 10 with Nelson's syndrome, and four eucorticoid patients were studied by light microscopy, immunoperoxidase, and electron microscopy. Seventy nine percent of all tumors and 70% of Nelson's cases were microadenomas, sometimes minute. A contiguity between the posterior lobe and the adenoma was seen in ten cases. Spontaneous infarction of the tumor with remission of Cushing's syndrome occurred in one case. Light microscopy revealed that the adenoma cells were basophilic and contained PAS-positive granules also staining with Herlant tetrachrome and lead-hematoxylin. The granules stained positively with antiserum to adrenocorticotrophic hormone (ACTH), beta-lipotropic hormones (beta-LPH) and beta-endorphin. The most characteristic ultrastructural finding was the presence of perinuclear bundles of microfilaments found in all our cases. Oncocytic changes were seen in three tumors. Four silent corticotroph adenomas, two of them originally microadenomas that had enlarged to enclosed adenomas while being treated with bromocriptine for hyperprolactinemia and one a large diffuse invasive tumor, did not differ in their microscopic, immunocytological, or ultrastructural features.
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PMID:Human corticotroph cell adenomas. 303 31

Pituitary adenomas may remain intrasellar or infiltrate dura and bone. Invasive adenomas are not considered to be malignant; in biological behavior they are between non-infiltrative adenomas and pituitary carcinomas. The latter are defined as tumors with subarachnoid, brain, or systemic metastasis. Invasion may be defined radiologically, operatively, or histologically. On the basis of operatively assessed tumor size and gross invasion of dura and bone as well as immunocytochemical and ultrastructural analysis of 365 pituitary adenomas, the following data were obtained. There were 23 growth hormone (GH)-cell adenomas: 14% microadenomas and 86% macroadenomas; their overall frequency of invasion was 50%. There were 24 prolactin (PRL)-cell adenomas: 33% microadenomas and 67% macroadenomas, with an overall frequency of invasion of 52%. Mixed GH-cell and PRL-cell adenomas were found in 35 cases; 26% were microadenomas and 74% were macroadenomas, and the overall frequency of invasion was 31%. Sixty patients had adrenocorticotropic hormone (ACTH)-cell adenomas (Cushing's disease): 87% microadenomas and 13% macroadenomas; the overall frequency of invasion was 25% (in 8% of microadenomas and 62% of macroadenomas). Twenty patients had ACTH-cell adenomas (Nelson's syndrome): 30% microadenomas and 70% macroadenomas; the overall frequency of invasion in these cases was 50% (in 17% of microadenomas and 64% of macroadenomas). Silent ACTH-cell adenomas, 100% macroadenomas, were found in 11 patients, with an 82% frequency of invasion. There were 32 follicle-stimulating and luteinizing hormone adenomas, all macroadenomas, with a frequency of invasion of 21%. Four patients had thyroid-stimulating hormone adenomas, all macroadenomas, with a 75% frequency of invasion. Null-cell adenomas were found in 93 cases: 2% microadenomas and 98% macroadenomas, with a frequency of invasion of 42%. There were 63 plurihormonal adenomas (GH, PRL, glycoprotein): 25% microadenomas and 75% macroadenomas, with a 50% overall frequency of invasion. Based on this study, and on their usual frequency of occurrence, the estimated rate of gross invasion by pituitary adenomas of all types is approximately 35%. It is concluded that immunocytochemical and ultrastructural characteristics of pituitary adenomas reflect the tendency of these tumors to infiltrate and hence may be of prognostic significance.
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PMID:Pathology of invasive pituitary tumors with special reference to functional classification. 309 6

Severe Cushing's syndrome developed in a man of 35 years. Plasma ACTH and lipotrophin hormone levels were supranormal, and dexamethasone failed to stop their production. An ACTH-producing thymic carcinoid tumour was found to be responsible for the Cushing's syndrome. The tumour tissue contained pro-opiomelanocortin (POMC)-mRNA and POMC-related peptides. In addition, human corticotrophin-releasing hormone (h-CRH) (0.25 ng/mg wet tissue) was identified in the tumour extract. Among a series of extracts from two normal and three tumoral (Nelson's syndrome) pituitary glands, six non-pituitary POMC-producing tumours and five normal thymuses examined, only the extract from the thymic tumour of our patient contained h-CRH. The molecule isolated had the same properties as synthetic h-CRH (dilution, Sephadex G 50 chromatography). Circulating h-CRH levels, however, were normal. The possible involvement of such ectopic CRH production in the aetiology of Cushing's syndrome remains uncertain.
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PMID:Characterization of human corticotrophin-releasing hormone and pro-opiomelanocortin-related peptides in a thymic carcinoid tumour responsible for Cushing's syndrome. 326 77

A rare cause of Cushing's syndrome appearing to originate in the adrenal glands is primary pigmented nodular adrenocortical disease (PPNAD). It may be variably associated with a complex of other pathologic characteristics that include cardiac myxomas, cutaneous myxomas, and lentigines, mammary myxoid lesions, testicular tumors, pituitary adenomas, and neuroectodermal tumors. We have reviewed the clinical, biochemical, radiographic, operative, and pathologic details of seven patients with PPNAD who have been evaluated at Mayo Clinic. Biochemical testing supported autonomous adrenal hyperfunction. This was based on the failure of cortisol suppression by high-dose dexamethasone, failure of pituitary stimulation by metyrapone administration, either normal or suppressed basal adrenocorticotropic hormone (ACTH) levels, normal radiographic studies of the sella turcica, and normal abdominal and thoracic computerized tomography in search of an ectopic ACTH-producing tumor. Six patients underwent bilateral total adrenalectomy without postoperative complications. Nelson's syndrome has not occurred, but acute adrenocortical insufficiency may have contributed to the death of one patient. To recognize the possible diagnosis of PPNAD preoperatively is important to proceed directly with adrenalectomy, avoiding unnecessary pituitary surgery. Moreover, if PPNAD is part of the broader pathologic complex, the possible presence of cardiac myxomas that may be multiple, recurrent, in atypical locations, and familial must be borne in mind.
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PMID:Primary pigmented nodular adrenocortical disease: diagnosis and management. 378 76

Immunoreactive alpha-MSH was found in human plasma and in normal subjects ranged from less than 10-45 pg/ml. Plasma alpha-MSH concentrations were within the normal range in 13 out of 15 subjects during the last trimester of normal pregnancy and only just outside the normal range in the remaining two. Elevated plasma alpha-MSH concentrations were found in 6 of the 11 patients with Nelson's syndrome and in 10 of the 11 patients with pituitary dependent Cushing's disease. Separation on high pressure liquid chromatography (HPLC) revealed two major peaks of immunoreactivity. These peaks, which were identified as des-acetyl alpha-MSH and alpha-MSH were similar in size in normal subjects and Cushing's disease. In Nelson's syndrome, on the other hand, there was a greater proportion of des-acetyl alpha-MSH and it is possible that this peptide is secreted from tumour cells of anterior lobe origin. Although there was no correlation between the circulating alpha-MSH and the degree of pigmentation the high concentrations of plasma immunoreactive alpha-MSH in Cushing's disease and the HPLC profiles in Nelson's syndrome could provide useful information as to the localization of the defects in these particular disorders.
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PMID:The measurement and characterisation by high pressure liquid chromatography of immunoreactive alpha-melanocyte stimulating hormone in human plasma. 407 73

In 14 cases of ACTH-producing pituitary adenomas (8 cases of Cushing's disease and 6 cases of Nelson's syndrome) dispersed cells prepared from adenoma tissue were incubated in a superfusion or static incubation system and investigated for ACTH, beta-endorphin (beta-EP) and beta-lipoprotein (beta-LPH) production. Effects of cortisol and lysine vasopressin (LVP) were evaluated. During the superfusion a qualitatively parallel secretory pattern is obtained for all hormones. Quantitatively, however, the response to LVP stimulation is more pronounced for beta-endorphin-like immunoreactivity (beta-LPH/beta-EP-IR) causing ACTH/beta-LPH/beta-EP-IR ratios to change throughout single experiments. beta-EP/beta-LPH ratios, however, which were estimated by means of Sephadex G-50 gel chromatography at various key points of the superfusion, were constant for each tumor, although variable between different adenomas, ranging from 0.68 to 2.0. The results suggest neither a differential control for the secretion of the peptides investigated within individual tumors nor a direct effect of cortisol or LVP on pro-opiomelanocortin processing. Summarizing clinical data and in vitro findings such as secretory behavior or hormone ratios, we can find no characteristic differences between Nelson's syndrome and Cushing's disease.
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PMID:In vitro secretion of pro-opiomelanocortin (POMC) derived peptides in human ACTH-producing pituitary adenomas: evaluation of hormone ratios in different functional states. 609 71

beta-Endorphin31, beta-endorphin1-27, and their alpha-N-acetyl derivatives were specifically separated by ion exchange chromatography from human beta-endorphin-'like' material obtained from extracts and culture media of corticotropic adenomas and extract of plasma from Nelson's syndrome and ectopic ACTH/LPH syndrome. Studies with pituitary-derived materials have shown that human beta-endorphin1-31 was the major form and human beta-endorphin1-27 a minor form. No other peptide was detected. In plasma from the ectopic ACTH-LPH syndrome human beta-endorphin1-31 was the only detected peptide. In 2 such patients with chronic elevation of human beta-endorphin1-31 the pain sensitivity threshold was normal and naloxone induced no modification, suggesting that circulatory human beta-endorphin has no effect on the central nervous system.
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PMID:Molecular forms of beta-endorphin in ACTH/LPH hypersecretion syndromes in man. 609 55

Six patients with Nelson's syndrome were given sodium valproate with or without diazepam for 3 or 5 weeks. Initial high plasma adrenocorticotropic hormone (ACTH) concentrations were greatly reduced by treatment and returned to high levels when treatment was stopped. Diazepam did not add significantly to the effects of sodium valproate alone. Three patients reported a decrease in the severity and frequency of headaches while on sodium valproate. In five patients abnormal skin pigmentation was reduced. Sodium valproate is a gamma-aminobutyric acid (GABA) transaminase inhibitor and it is suggested that the drug raises GABA levels in the hypothalamus and that this is responsible for the reduction in ACTH secretion. The data are consistent with the hypothesis that Nelson's syndrome is a neuroendocrine disease caused by a deficiency in the hypothalamic GABA-ergic system.
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PMID:Effect of treatment with sodium valproate and diazepam on plasma corticotropin in Nelson's syndrome. 611 28


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