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)

A 24-year-old woman with severe Cushing's syndrome was found to have corticotroph cell pituitary adenoma arising within a benign cystic ovarian teratoma. The patient manifested sustained hypercortisolemia and lack of suppression of either adrenocorticotropin (ACTH) or cortisol production. There was no evidence of a pituitary mass or secretion of other hormones. After careful clinical evaluation, no other tumor masses were found. Resection of the ovarian tumor led to normalization of ACTH and cortisol levels. Densely granulated corticotroph tumor cells with prominent Type I microfilaments and intracytoplasmic ACTH immunoreactivity characterized the neoplasm as a pituitary corticotroph cell adenoma. This is, to our knowledge, the first case reported of a functioning pituitary adenoma arising within a benign cystic teratoma.
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PMID:Corticotroph cell pituitary adenoma within an ovarian teratoma. A new cause of Cushing's syndrome. 354 46

Immunohistochemical and histological investigations were undertaken on 24 surgically-removed pituitary adenomas. By histology (haemalu-eosin staining), 7 chromophobe, 12 acidophil and 5 basophil pituitary adenomas were revealed. For immunohistochemical purposes the peroxidase-antiperoxidase technique was applied. Primary antisera against 10 hormones were used. By immunohistochemistry, 7 prolactin-containing, 2 TSH-containing, 2 GH-containing and 1 beta-endorphin-containing pituitary adenomas were identified. Furthermore, 1 mixed thyrotropic-prolactin human pituitary adenoma was detected. A possible connection between histological and immunocytochemical findings is discussed.
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PMID:Immunocytochemical characterisation of human pituitary adenomas. 391 65

To clarify whether various neuropeptides found in the hypothalamus act directly on a pituitary adenoma causing Nelson's syndrome, we examined the influence of these peptides on the secretion of immunoreactive ACTH, beta-endorphin, and melanotropins, the proopiomelanocortin (POMC)-derived peptides, by the cultured pituitary adenoma from a patient with Nelson's syndrome. Results showed that somatostatin-14 and somatostatin-28 suppressed the secretion of POMC-derived peptides by the adenoma and that somatostatin-28 was as potent as somatostatin-14. Other neuropeptides such as arginine vasopressin, vasoactive intestinal polypeptide, and oxytocin stimulate the secretion of POMC-derived peptides. Substance P, TRF, Met-enkephalin and Leu-enkephalin were also found to modulate the secretion of POMC-derived peptides. This suggests that the adenoma may have multiple receptors to various neuropeptides.
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PMID:Effects of various neuropeptides on the secretion of proopiomelanocortin-derived peptides by a cultured pituitary adenoma causing Nelson's syndrome. 612 87

Fragments of the pituitary adenoma of a patient with Cushing's disease were maintained in defined culture medium. Immunoreactive (IR) ACTH, IR alpha-MSH, IR beta-lipotropin (beta-LPH), IR beta-endorphin, and IR gamma-MSHs secreted from the adenoma were studied with gel permeation chromatography and the respective RIAs. The adenoma secreted roughly equimolar quantities of IR beta-LPH plus IR beta-endorphin, IR gamma 3-MSHs, and IR ACTHs. It also secreted IR alpha-MSH as well as IR gamma 1-MSH, although in a much lower concentration than the above four peptides. The secreted gamma 3-MSH-like peptides were found to be glycosylated. The secretion pattern suggests that this particular adenoma processes the pro-opiomelanocortin molecule in pathways which encompass those of both the pars distalis and the pars intermedia.
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PMID:Secretion pattern of pro-opiomelanocortin-derived peptides by a pituitary adenoma from a patient with Cushing's disease. 625 45

Five corticotropin-producing tumours were examined for peptides related to the corticotropin-beta-lipotropin precursor. Two were basophil pituitary adenomas and three were bronchial carcinoids. The cells of the two pituitary adenomas stained with antisera against beta-endorphin and against pro-gamma-melanotropin, the NH2-terminal fragment of the corticotropin-beta-lipotropin precursor, but not with antisera against alpha-melanotropin or beta-lipotropin. The corticotropin-storing tumor cells of the bronchial carcinoids stained with antisera against beta-endorphin, beta-lipotropin or pro-gamma-melanotropin. Only one of the three bronchial carcinoids contained cells reacting with the antiserum against alpha-melanotropin. Although the two types of corticotropin-storing tumours (pituitary adenoma and bronchial carcinoid) differed with respect to beta-lipotropin content, the over-all picture indicates that the proteolytic processing of the corticotropin precursor proceeds along similar lines in tumour cells and in pituitary corticotrophs. An acetic acid extract of one of the bronchial tumours was subjected to gel chromatography and immunochemical analysis of material related to pro-gamma-melanotropin. The immunoreactive material displayed a considerable size heterogeneity, with the predominant components having a molecular weight larger than that of authentic pro-gamma-melanotropin.
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PMID:Evidence for the presence of pro-gamma-melanotropin, the NH2-terminal fragment of the corticotropin-beta-lipotropin precursor, in corticotropin-producing tumours. 627 99

A pituitary tumor from a patient with severe Cushing's disease and marked hyperprolactinemia was extensively studied by immunohistochemical techniques. Tissues from two separate areas of the adenoma were found to contain similar cell proportions of PRL as well as ACTH and related peptides (beta-lipotropin, beta-endorphin, and alpha MSH). The tumor was composed of approximately 70% immunoreactive PRL cells and 5% ACTH-containing cells. Double immunostaining revealed that PRL or ACTH and related peptides were found in two distinct populations of tumor cells. These results document for the first time inappropriate synthesis and secretion of an unusual combination of pituitary hormones from a mixed pituitary adenoma.
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PMID:Concurrent production of adrenocorticotropin and prolactin from two distinct cell lines in a single pituitary adenoma: a detailed immunohistochemical analysis. 628 57

Pituitary adenomas were found in 21 (84%) of 25 dogs with spontaneous pituitary-dependent hyperadrenocorticism. Six dogs had pars intermedia adenomas, whereas 15 had tumours of the pars distalis. Diffuse corticotroph cell hyperplasia was found in 1 of the 4 pituitaries without adenoma; in 2 dogs with pituitary adenoma, coexisting hyperplasia of the surrounding corticotrophs was also present. Immunocytochemical staining of the pituitaries revealed positive staining for ACTH, beta-lipotrophin, and beta-endorphin in the majority of both pars distalis and pars intermedia adenomas. The most frequent and intense staining was found with anti-beta-endorphin. In most part intermedia tumours, many cells stained strongly for alpha-MSH; double immunostaining of one pars intermedia adenoma for ACTH and alpha-MSH showed that some tumour cells stained only for ACTH or alpha-MSH whereas others contained both peptides. Only occasional cells stained for alpha-MSH in pars distalis adenomas.
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PMID:Immunocytochemical study of the hypophysis in 25 dogs with pituitary-dependent hyperadrenocorticism. 628 90

A beta-endorphin (beta END)-containing pituitary adenoma was demonstrated by immunocytochemical, biochemical, and ultrastructural methods in a 43-yr-old man who had impotence, slight testicular atrophy, and an enlarged sella turcica (grade II0), but no manifestations of Cushing's disease. Preoperative hormone data revealed hyperprolactinemia (97 ng/ml), low plasma cortisol levels without circadian rhythm, undetectable plasma ACTH, and normal plasma FSH and LH levels, with an impaired response to LRH. After hypophysectomy, these hormone levels normalized and responded normally to dynamic tests. Immunocytochemically, 30% of the tumor cells reacted only with beta END antiserum. beta END immunoreactivity was the only component revealed by RIA and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A characteristic ultrastructural aspect is also described. These findings demonstrate dissociation in the secretion of the proopiomelanocortin-derived peptides and suggest a relationship between hyperprolactinemia and tumor secretion of beta END.
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PMID:A human beta-endorphin pituitary adenoma. 631 45

A large endocrine active pituitary adenoma causing a Cushing's syndrome was investigated for the presence of subunits of the corticotropin-lipotropin precursor by immunohistology. A quantitative study revealed immunoreactivity (ir) for ACTH in 87.1% of the adenoma cells, beta-lipotropin-ir in 77.1%, beta-endorphin-ir in 75.3%, alpha-MSH-ir in 22.9% and methionine-enkephalin-ir in 7.8%. The adjacent distal pituitary gland showed a six-fold increase of prolactin-ir cells indicating the release of biologically active endogenous opiates. The strong alpha-MSH-ir within the adenoma cells in contrast to those of the distal pituitary may signify that alpha-MSH was being secreted by the adenoma. The proportions of other endocrine cell types within the anterior pituitary were normal (3.1% corticotrophs, 49.4% somatotrophs, 8.2% gonadotrophs and 7.1% thyrotrophs). 0.5% of the cells of the distal pituitary and 0.1% within the adenoma were VIP-ergic, which may be due to a vasoregularitory system and/or be involved in prolactin release.
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PMID:An immunoperoxidase study of a human pituitary adenoma associated with Cushing's syndrome. 632 62

The effects of synthetic ovine corticotropin-releasing factor (oCRF), arginine vasopressin (AVP), alpha-melanocortin (alpha MSH), and dexamethasone on the release of pro-opiomelanocortin (POMC)-related peptides were studied on a pituitary adenoma of a patient with Nelson's syndrome. CRF, at doses up to 100 ng/ml, has no effect on IR-ACTH, IR-hNT or IR-beta LPH secretion by the pituitary adenoma cells within the first week of monolayer culture. During the second week of in vitro conditions, however, the cells responded to oCRF (1-100 ng/ml) with a significant increase in all three POMC-related peptides. AVP (10 and 100 ng/ml) was effective in stimulating secretion of the three POMC-related peptides on day 6 in vitro; in addition, during the second week in culture, AVP (1 ng/ml) acted synergistically with 1-100 ng/ml of oCRF to release IR-ACTH, IR-hNT and IR-beta LPH at least 3-4 fold higher than CRF alone. alpha MSH (10 micrograms/ml) and dexamethasone (10(-6)M) did not alter the release of any of the three peptides. These results demonstrate that CRF and AVP can act synergistically on human pituitary tissue in vitro to promote the release of POMC-related peptides and also in vivo as shown by others.
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PMID:Synergistical effects of ovine corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) on the release of pro-opiomelanocortin (POMC) related peptides by pituitary adenoma of a patient with Nelson's syndrome in vitro. 633 68


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