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)

Methionine(met)-enkephalin immunoreactivity as visualized by the peroxidase-antiperoxidase procedure, is present in spermatogonia, spermatocytes, spermatids, and young ovarian follicles of Locusta (panoistic type) and Sarcophaga (polytrophic type). Follicle cells and mature spermatozoa are always immunonegative as are locust vitellogenic follicles. In oocytes and in trophocytes, the met-enkephalin-like material first appears around the nucleus and is then dispersed throughout the cytoplasm. Later, it is present only in the periphery. In the ovary of both insects, no immunoreactivity is found with antisera against adrenocorticotrophic hormone, melanophore stimulating hormone, beta-endorphin, corticotropin releasing factor, or leucine-enkephalin. All these antisera yield a positive reaction when applied to the central nervous system as does the met-enkephalin antiserum. This study indicates that the met-enkephalin-like peptide may play a role in reproductive physiology.
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PMID:Methionine-enkephalin immunoreactivity in the gonads and nervous system of two insect species: Locusta migratoria and Sarcophaga bullata. 336 Feb 84

Parathyroid hormone (PTH) receptors have been found in a subpopulation of kidney cells. In this report, we investigated the feasibility of techniques that apply a partial antagonist of PTH conjugated to biotin to localize receptors cytochemically on bovine kidney cortical cells in monolayer culture at the light microscopic level. Biotinylated bovine PTH (1-84) (biotinyl-PTH) was bound to the cultured cells for 1-30 min at 37 degrees C in the amounts of 10(-5) -10(-10) M. In a different set of experiments, the cells were also exposed to a solution containing 10(-6) M biotinylated PTH and an excess of unlabeled PTH, insulin, adrenocorticotropin, or calcitonin for 10 and 30 min at 37 degrees C to test the specificity of the binding. The cells were then fixed in 2.5% glutaraldehyde and stained with the avidin-biotin peroxidase complex (ABC) technique. Diffuse labeling was evident on 30% of the cells in 10 min with concentrations of biotinyl-PTH as low as 10(-8) M. The stain was diffuse, but more intense after 1-10 min in higher concentrations (10(-6) M). If a 15-1500-fold excess of unlabeled PTH was added to the biotinyl-PTH, no staining was observed. The other peptides (insulin, ACTH or calcitonin) had no effect on binding. Longer times in biotinyl-PTH (10(-6) M for 10-30 min) resulted in intense patches of label on the cells resembling caps (in addition to the pale diffuse label). The percentage of labeled cells in the monolayer (30%) did not change with time. These studies show that a partial antagonist of PTH can be used as a cytochemical probe for specific PTH receptors in a subpopulation of cultured cortical kidney cells.
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PMID:Visualization of binding sites for bovine parathyroid hormone (PTH 1-84) on cultured kidney cells with a biotinyl-b-PTH (1-84) antagonist. 351 93

Neuroendocrine (NE) neoplasms range from well to poorly differentiated types. These neoplasms usually contain neurosecretory (NS) granules demonstrated by either transmission electron microscopy (TEM) or silver reduction methods. By using the uranaffin reaction, one can differentiate NSG from other membrane-bound organelles. Recently, a variety of antibodies reactive against specific peptides or neurotransmitter substances have been advocated as being diagnostically useful. Using the peroxidase-anti-peroxidase (PAP) or Avidin-Biotin technics, we studied 41 NE neoplasms using anti-sera specific for neurospecific enolase (NSE), bombesin, adrenocorticotropic hormone (ACTH), calcitonin, and serotonin. All cases were shown to contain NS granules with a positive uranaffin reaction. In all 25 well-differentiated cases, at least one anti-serum gave a positive reaction. NSE was positive in 22 of the 25. In the poorly differentiated group, 7 (43.2%) of 16 were negative for all anti-sera tested. In these negative cases TEM using the uranaffin reaction remains an important diagnostic test.
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PMID:Comparison of the usefulness of histochemistry and ultrastructural cytochemistry in the identification of neuroendocrine neoplasms. 375 79

The distribution of immunoreactive corticotropin-releasing hormone (CRF) in the forebrain and pituitary of the frog Rana ridibunda was studied by means of specific radioimmunoassay and immunohistochemistry using the indirect immunofluorescence and the peroxidase-antiperoxidase techniques. Relatively high concentrations of CRF-like material were found in both chiasmatic and infundibular regions of the hypothalamus (352 +/- 11 and 422 +/- 36 pg, respectively). Large amounts of CRF were also found in neurointermediate lobe extracts. Standard curves of synthetic CRF and the dilution curves for hypothalamic or neurointermediate lobe extracts were parallel. After Sephadex G-75 gel filtration, CRF-like immunoreactivity eluted in a single peak, in the same position as synthetic ovine CRF. Reversed-phase high-performance liquid chromatography of the material purified on Sephadex G-75 revealed 5 components with CRF-like immunoreactivity. The major peak had a retention time of 22 min as compared to 25.4 min for ovine CRF and 36 min for rat CRF. The detection of CRF-like immunoreactivity in neurons was facilitated by colchicine pretreatment of the frogs. The great majority of the CRF-positive perikarya were seen in the ventral region of the preoptic nucleus. A few scattered perikarya were also observed in the dorsal preoptic nucleus and in the retrochiasmatic region. Immunoreactive fibers were found in the infundibular nucleus and in various extrahypothalamic zones. CRF-containing neurons were apparently distinct from mesotocinergic and vasotocinergic neurons. A large number of immunoreactive nerve fibers were observed in the median eminence in close contact with the capillaries of the pituitary portal plexus and in the neural lobe. A few CRF-positive fibers were detected in the intermediate lobe, whereas the distal lobe was totally negative. These results show that the diencephalon and pars intermedia-nervosa of the frog contain a peptide immunologically related to mammalian CRF.
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PMID:Immunohistochemical localization and radioimmunoassay of corticotropin-releasing factor in the forebrain and hypophysis of the frog Rana ridibunda. 388 12

A morphologic, histochemical, and immunocytochemical study of 20 cases of pure gastrointestinal carcinoids, adenocarcinomas, and mixed neoplasms composed of both elements, so-called composite carcinoma-carcinoid tumors (CCC), was undertaken in order to correlate the morphologic patterns with the immunocytochemical localization of carcinoembryonic antigen (CEA), serotonin, and a battery of polypeptide hormones (calcitonin, glucagon, insulin, gastrin, somatostatin, and adrenocorticotropin [ACTH]). Paraffin sections from five pure carcinoids, seven pure adenocarcinomas, and eight CCC from the stomach, small bowel, appendix, and colon were studied with mucicarmine, silver impregnation stains, and a peroxidase-anti-peroxidase technic. Of the eight CCC, all were mucin positive, four were argyrophilic, and three were argentaffin positive. CEA was present in all eight, serotonin in seven, and calcitonin in one. No other neurohormonal peptides were demonstrated. The distribution of serotonin and CEA generally corresponded to the morphologic pattern, but discordance was observed in two cases, i.e., serotonin was not always localized to areas of carcinoid and CEA not always confined to areas of carcinoma. All five pure carcinoids demonstrated intracytoplasmic localization of serotonin, whereas none contained intracytoplasmic CEA. In two cases, CEA was present within acinar lumens only. The seven colonic adenocarcinomas were argyrophil and argentaffin negative. All contained CEA within the cytoplasm and in gland lumens. None contained serotonin. None of the neurohormonal peptides was localized in either pure adenocarcinomas or carcinoids. This study reveals that among gastrointestinal neoplasms displaying morphologic patterns of adenocarcinoma and carcinoid, immunocytochemical localization of CEA and serotonin confirms their bidirectional differentiation and justifies the designation "composite carcinoma-carcinoid."
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PMID:Composite carcinoma-carcinoid tumors of the gastrointestinal tract. A morphologic, histochemical, and immunocytochemical study. 389 86

Serial semithin sections of rat neurohypophysis were immunostained with 2 antibodies to enkephalins using the peroxidase antiperoxidase method. One of the antibodies (R133) recognizes both met- and leu-enkephalin whereas the other (R26) reacts with met-enkephalin only. After cyanogen bromide pretreatment of the sections the antibody R133 stained only a subpopulation of nerve endings that were distinct from those stained with the latter antibody. R26-(met-enkephalin-like) immunoreactivity was totally abolished by cyanogen bromide pretreatment. This preincubation method which selectively interferes with the staining of met-enkephalin terminals may help to discriminate the two enkephalins in immunocytochemical preparations.
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PMID:Cyanogen bromide cleavage of methionine residues as a control method for enkephalin immunocytochemistry. 390 10

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

Neuronal pathways containing alpha-melanocyte-stimulating hormone (alpha-MSH) extending from the zona incerta and lateral hypothalamic area to the inferior colliculus and spinal cord were analyzed using both immunohistochemical localization and a retrograde tracer. Biotinized horseradish peroxidase injected into the inferior colliculus or the thoracic cord of the rat labeled a number of neurons in the zona incerta and lateral hypothalamic area. Simultaneous immunostaining of the same sections with alpha-MSH antiserum showed that some of these neurons are alpha-MSHergic.
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PMID:The descending alpha-MSHergic (alpha-melanocyte-stimulating hormone-ergic) projections from the zona incerta and lateral hypothalamic area to the inferior colliculus and spinal cord in the rat. 402 3

A biotin-conjugated synthetic corticotropin releasing factor (B-CRF) was prepared and characterized. Its biological activity and binding affinity were compared with that of unlabeled synthetic CRF. Both forms of the releasing factor were equipotent in in vitro studies measuring the release of corticotropin (ACTH) (ED50 = 1 nM). The IC50 in the binding assays was 1.5 nM for CRF and 4 nM for B-CRF. Dual avidin-biotin peroxidase complex stains were then used in pituitary monolayer cultures to visualize receptivity to the releasing factor and to confirm opiocortin storage in the target cells. All corticotropes showed stain for B-CRF. The percentage of cells that were double-labeled for ACTH and CRF increased with the dose of B-CRF during a four hour incubation period. The CRF stain was abolished, however, when an excess of unlabeled CRF was added to compete with B-CRF. The distribution of the B-CRF and ACTH stains varied in the cells with the time of exposure to the analog. These studies show that biotin-conjugate CRF is a potent analog that can be demonstrated cytochemically on cells identified immunocytochemically as corticotropes. It can be used to follow important events associated with CRF stimulation including the rapid internalization of CRF coupled with the mobilization of corticotropin stores and the formation of cellular processes.
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PMID:Characterization of a potent biotin-conjugated CRF analog and the response of anterior pituitary corticotropes. 608 48

A soluble somatostatin binding factor was detected in cell-free extracts from chicken pancreas. For binding measurements Tyr1-somatostatin was radio-labeled with 125I by the lactoperoxidase technique. Specific radioactivity of about 18.5 MBq/nmol was achieved. Maximal total binding is approximately 0.17 (B/T) in the presence of 30 mg/l pancreatic protein. The specific binding is 0.10 and is suppressed by addition of 1 mg/l synthetic cold cyclic somatostatin. The dose-response curve of synthetic cyclic somatostatin is in the range of 0.6-600 nmol/l. Ca2+ and reduced thiol-reagents inhibit the specific binding. Insulin, glucagon and corticotropin show a low, and luliberin and reduced somatostatin a high cross-reactivity. Molecular weight was estimated by gel filtration and the specific binding molecule was eluted at a Kav = 0.2 on an Ultrogel (AcA 54) column. This corresponds to Mr 40 000. Electrophoretic properties of the binding complex and semipurification by polyacrylamide disc gel electrophoresis: relative mobility of the 125I-Tyr-somatostatin binding complex is about 0.6. Relative mobilities of binding-protein fractions are 0.71 and 0.74. Highest relative specific binding was detected in the (100 000 g) cytosol fractions. Binding with cell-free extracts from the splenic lobe area was 4-fold higher than that from other parts of the chicken pancreas.
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PMID:Somatostatin binding factor from chicken pancreas. 611 81


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