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)

N-Terminal (1-76) portion of proopiomelanocortin (hNT) was measured in normals, Addison's, Nelson's, Cushing's disease, and in dexamethasone suppressible hyperaldosteronism (DSH) by using a specific homologous RIA. Mean basal immunoreactive hNT level was 94.2 +/- 6 pg/ml (mean +/- SE) in normal subjects. In Cushing's disease hNT values were slightly but not significantly (121 +/- 26.5 pg/ml) higher. In patients with DSH the levels were within normal range while they were much higher in Addison's and Nelson's syndromes. A strong correlation was found between IR-hNT and ACTH in plasma of normal subjects and patients with different disorders of the pituitary-adrenal axis (r = 0.83, p less than 0.01). Corticotropin-Releasing-Hormone (CRH) test in Cushing's disease stimulated the release of both ACTH and IR-hNT, showing a slightly different pattern of secretion. Similar patterns of secretion were found for hNT and ACTH in various pituitary-adrenal abnormalities. Normal levels of hNT in DSH do not support a role of this peptide in the pathogenesis of the disorder. Measurement of hNT in plasma can provide an additional tool for the diagnosis of patients with various disorders of the hypothalamic-pituitary-adrenal axis.
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PMID:Pro-gamma-MSH levels in various disorders of pituitary-adrenal axis. 215 20

A 44-yr-old man with hypocortisolism was shown to have an undetectable basal plasma ACTH level and absent or subnormal ACTH and beta-lipotropin responses to provocative testing with insulin, vasopressin, and CRH. Endocrine function after glucocorticoid replacement was otherwise normal, thus establishing the diagnosis of isolated ACTH deficiency. This patient's serum was tested immunohistochemically for the presence of an antipituitary antibody by indirect immunofluorescence of rat pituitary tissue. Positive immunostaining was observed in stellate-shaped cells in the anterior and intermediate lobes. Immunopositive cells were shown by immunoelectron microscopy to have ultrastructural characteristics of corticotrophs. Immunoreactivity was concentrated in secretory granules 120-170 nm in diameter. In a double immunolabeling procedure, staining by the patient's serum was shown to colocalize with rabbit antiserum to ACTH, but not with antisera to PRL, GH, beta TSH, or beta LH. Immunoabsorption of the patient's serum with ACTH-(1-24), ACTH-(1-39), gamma MSH, corticotropin-like intermediate lobe peptide, beta-endorphin, or beta-lipotropin failed to diminish immunolabeling in the pituitary. We conclude that the antipituitary antibody in this patient's serum shows immunohistochemical specificity for a rat corticotroph antigen located in secretory granules that is neither ACTH nor any of the proopiomelanocortin (POMC)-derived peptides tested. The autoantigen could be a cell-specific granular factor involved in the posttranslational processing of POMC or secretion of ACTH. We postulate that an autoimmune process may account for this patient's disease, and that his antipituitary antibody could play a pathogenic role by either inhibiting a POMC-processing enzyme or initiating an antibody-dependent cell-mediated cytotoxicity reaction, resulting in the selective destruction of corticotrophs.
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PMID:Isolated adrenocorticotropin deficiency associated with an autoantibody to a corticotroph antigen that is not adrenocorticotropin or other proopiomelanocortin-derived peptides. 215 84

In teleost fishes, the melanotropes of the neurointermediate lobe of the pituitary gland release numerous peptides--adrenocorticotropin (ACTH), melanotropin (MSH), lipotropin (LPH), corticotropin-like intermediate lobe peptide (CLIP), and endorphin--which are derived from the precursor molecule proopiomelanocortin. Superfused, isolated, dispersed goldfish neurointermediate lobe cell columns were used to investigate the release of immunoreactive (ir) alpha-MSH and ir ACTH from goldfish melanotropes. Stimulation of neurointermediate lobe cell columns with pulses of the structurally homologous peptides, Catostomus urotensin I (UI), ovine corticotropin-releasing factor (oCRF), or sauvagine, produced a significant increase in the concomitant release of ir alpha-MSH and ir ACTH. UI was two to three times as potent as ovine CRF or sauvagine. These studies suggest that CRF- and UI-like peptides stimulate the secretory activity of teleost melanotropes.
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PMID:CRF, urotensin I, and sauvagine stimulate the release of POMC-derived peptides from goldfish neurointermediate lobe cells. 216 77

E. coli strains producing a hybrid protein, containing adrenocorticotropic hormone (ACTH) and protein A of S. aureus was obtained. The sequence coding for ACTH was obtained from the bovine proopiomelanocortin cDNA and, after the modification of the 5'- and 3'-terminal parts, was linked with the protein A gene and its derivatives due to synthetic adaptors. Three forms of ACTH gene, coding this hormone with differing N-terminal amino acid were used to construct the fusion gene. The hybrid proteins contain Asp-Pro or (Asp)4-Lys sequences for obtaining ACTH by acid or enterokinase treatment, respectively. It is shown that each of the constructed plasmids direct the synthesis of hybrid protein in E. coli. This protein was purified by the use of IgG-sepharose. The level of the expression of the hybrid protein is 4 mg/l of the bacterial culture. Most of the synthesized protein is secreted into the periplasmic space.
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PMID:[Expression in Escherichia coli of hybrid genes containing sequences coding the bovine adrenocorticotropic hormone]. 216 93

We examined the effect of restraint on testicular interstitial fluid (TIF) concentrations of ACTH, beta-endorphin-lipotropin (beta-E-LI) and testosterone and correlated those changes with plasma concentrations of ACTH, beta-E-LI, corticosterone, LH and testosterone in adult rats. Animals were subjected to 1, 2, or 3 h of restraint and were killed immediately following the stress period. Plasma values of ACTH and beta-E-LI were elevated above control values after 1 and 2 h, but not after 3 h of restraint. Plasma corticosterone showed a similar response to restraint except that concentrations were also elevated after 3 h. Plasma testosterone concentrations were elevated after 1 h of restraint, but after 3 h of restraint had fallen below control values. Restraint reduced plasma testosterone concentrations without altering plasma LH concentrations. The decline in plasma testosterone during restraint was associated with a parallel decrease in testosterone in the TIF. Concentrations of ACTH and beta-E-LI were 6- and 3-fold greater in TIF than in the plasma. While 1 or 2 h of restraint did not affect ACTH and beta-E-LI in TIF, values of these hormones were elevated in rats exposed to 3 h of restraint. These data, coupled with recent reports that testicular proopiomelanocortin (POMC)-derived peptides may modulate testicular steroidogenesis, suggest that these factors may play an autocrine or paracrine role in mediating stressor-induced changes in testicular function.
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PMID:Effect of restraint stress on gonadal proopiomelanocortin peptides and the pituitary-testicular axis in rats. 216 75

We have transiently expressed the yeast KEX2 gene together with the proopiomelanocortin (POMC) cDNA in COS-1 cells. Characterization of the POMC-related immunoreactive peptides by gel permeation and reversed-phase high pressure liquid chromatography showed that the KEX2 enzyme was active and capable of carrying out cleavage of POMC to release the authentic maturation product beta-endorphin(1-31). Peptides resembling beta-lipotropin, the amino terminal glycopeptide, and ACTH(1-39) were also detected as major products in the cell extracts. Our results indicate that the KEX2 enzyme can proteolytically release from POMC a set of peptides similar to that normally found in interior pituitary.
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PMID:Intracellular proteolytic processing of proopiomelanocortin in heterologous COS-1 cells by the yeast KEX2 endoprotease. 216 11

After the recent demonstration of the facilitatory effect exerted by corticotropin-like intermediate lobe peptide (CLIP or adrenocorticotropic hormone (ACTH) 18-39) on paradoxical sleep in the rat (Chastrette and Cespuglio, 1985), we undertook the production of monoclonal antibodies against this peptide. Wistar rats were immunized against CLIP and their spleen cells fused with mouse myeloma cells. After recloning, 25 supernatants were found to give positive immunohistochemical reactions in the rat brain. In immunohistochemical tests performed by preabsorption, the 25 supernatants presented similar properties, i.e. recognized CLIP, ACTH (1-39) and ACTH (25-39), but not ACTH (1-24) and the C-terminal fragment (34-39). We assume that the epitope(s) recognized by the 25 supernatants is (are) located between the amino-acids Asn25 and Ala34 of the CLIP molecule. The immunoreactivity observed in the rat brain and hypophysis with this antibody was distributed with a pattern quite similar to that described for anti-ACTH antibodies. A main group of immunoreactive cell bodies was located in the mediobasal hypothalamus and a small group in the nucleus of the solitary tract. Immunoreactive fibres were distributed from the olfactory nucleus to the spinal cord and formed particularly rich networks in the hypothalamus and preoptic area. Among other locations, immunoreactive axons were also present in the brainstem centres involved in the control of the sleep-waking cycle, which is in accordance with the influence of CLIP on paradoxical sleep. Using Abercrombie's formula, the number of immunoreactive cells in the mediobasal hypothalamus was estimated at about 3000 neurons. We conclude that our monoclonal anti-CLIP antibody can be considered as a good marker of proopiomelanocortin neurons.
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PMID:A monoclonal antibody directed against CLIP (ACTH 18-39). Anatomical distribution of immunoreactivity in the rat brain and hypophysis with quantification of the hypothalamic cell group. 216 15

In order to elucidate whether pituitary peptides other than ACTH which are derived from the proopiomelanocortin (POMC) are involved for aldosterone secretion in primary aldosteronism, we administered ovine corticotropin releasing factor (CRF), beta-endorphin and naloxone to seven patients with aldosterone producing adenoma. One hundred micrograms of CRF produced an augmented aldosterone response in patients with aldosteronism, while 500 micrograms of beta-endorphin infusion failed to cause any significant changes in neither normal subjects nor patients. An opioid antagonist, naloxone (10 mg, iv) produced no noticeable change in plasma aldosterone in normal subjects, while it caused a slight increase in patients with primary aldosteronism. Plasma cortisol increased to a similar degree in response to CRF and naloxone in normal subjects and patients. In three patients with isolated ACTH deficiency, neither aldosterone nor cortisol responded to these stimuli. The present results indicate that POMC-derived pituitary peptides other than ACTH are unlikely to participate in the aldosterone secretion in normal subjects or in patients with primary aldosteronism.
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PMID:Pituitary peptides other than ACTH may not be aldosterone secretagogue in primary aldosteronism. 217 3

The growth of the mouse pituitary cell line AtT 20 was studied under different in vitro conditions. A completely defined, serum-free culture medium supported the survival of cells for a period of more than 2 mo. The medium, designed SFI, consisted of basal medium supplemented with transferrin, insulin, putrescine, and selenium. For maintenance of cells during long-term culture, no additional compounds were necessary. The time-dependent increases in cell number during culture with fetal bovine serum (FBS) and under serum-free conditions showed similar properties. Analysis of the effects of different substrata on cell growth demonstrated that polylysine supported adhesion and initial growth of cells to a greater extent than untreated plastic or FBS adsorbed to culture dishes. Synthesis and regulation of proopiomelanocortin (POMC)-mRNA, the precursor-mRNA of adrenocorticotropin (ACTH), could be detected by Northern blot analysis under basal conditions and after incubation with steroids and corticotropin-releasing hormone (CRH), indicating the serum-independent expression of important cellular properties.
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PMID:Serum-free culture of AtT 20 pituitary cells: a system for neuroendocrine studies under defined conditions. 217 66

Adenomas of the pars intermedia from 19 horses and normal pituitary glands from seven horses were evaluated histologically and immunocytochemically for adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), beta-endorphin (beta-END), proopiomelanocortin (POMC), prolactin, neuron specific enolase, and glial fibrillary acidic protein (GFAP). The 26 horses ranged in age from 7 to 31 years. Histologically, all adenomas had a uniform pattern characterized by cords of large columnar cells forming palisades and pseudoacini separated by a delicate fibrovascular stroma. Immunostaining of adenomas derived from the pars intermedia was similar to that of non-neoplastic equine pars intermedia. An immunocytochemical evaluation revealed a diffuse, strong cytoplasmic reaction for POMC, a moderate to strong reaction for alpha-MSH and beta-END, a weak reaction for ACTH, and negative immunostaining for prolactin, GFAP, and neuron specific enolase in the adenomas. The unique clinicopathologic syndrome that develops in horses with pituitary adenomas appears to be the result of an over-production of POMC-derived peptides in addition to space-occupying effects resulting in dysfunction of the hypothalamus and neurohypophysis.
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PMID:Immunocytochemical demonstration of proopiomelanocortin-derived peptides in pituitary adenomas of the pars intermedia in horses. 217 80


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