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)

The peroxidase-antiperoxidase immunocytochemical technique was used to identify the ACTH/endorphin cells in the porcine pituitary at the ultrastructural level and to determine the precise subcellular localization of the pro-ACTH/endorphin fragments. The cells display different aspects: 1) large, regular shapes with numerous and large secretory granules; 2) small, irregular and angular shapes with small granules aligned along the periphery of the cell; and 3) intermediate forms. The presence of alpha- and beta-endorphin not only in the same cells but also in the same secretory granules that contain ACTH and beta-LPH clearly indicates that both the precursor or its fragments and the above-mentioned peptides are stored in the same granules and released simultaneously by the corticotropic cells. The presence of FSH in some corticotropic cells is also discussed.
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PMID:Ultrastructural localization of corticotropin, beta-lipotropin, and alpha- and beta-endorphin in the porcine anterior pituitary. 611 64

The distribution of corticotropin releasing factor (CRF)-immunoreactive structures in the rat thalamus was studied after treatment with high doses of colchicine (100 micrograms/100 g b.wt.) with peroxidase-antiperoxidase (PAP) immunocytochemistry in vibratome sections. CRF-immunopositive perikarya were found in the 'posteromedial complex' of the thalamus, including the ventromedial, paracentral, mediodorsal, rhomboid, parafascicular nuclei, centrum medianum and ventromedial portion of the posterolateral nucleus. In addition, CRF-containing perikarya were observed in the pretectal and subthalamic nuclei. CRF-immunoreactive processes were seen in most of the medial nuclei of the thalamus. The presence of CRF-immunopositive structures in the thalamus suggests that CRF not only functions as a hypophysiotropic hormone regulating the release of ACTH and beta-endorphin from the pituitary, but also as a neurotransmitter or neuromodulator, playing an important role in nociception and analgesia.
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PMID:Immunocytochemical localization of corticotropin releasing factor (CRF)-like immunoreactivity in the thalamus of the rat. 615 62

Acrolein was examined as an alternative fixative to formaldehyde for immunocytochemical localization of neuropeptides in the rat brain. A brief (5 min) vascular perfusion with a 5% acrolein solution allowed the identification of thyrotropin-releasing hormone (TRH), vasoactive intestinal peptide (VIP), somatostatin (SRIF), neurotensin (NT), methionine enkephalin (Menk), adrenocorticotropic hormone (ACTH), tyrosine hydroxylase (TH), and luteinizing hormone-releasing hormone (LHRH) in fibers and perikarya within the central nervous system of the rat using the peroxidase-antiperoxidase (PAP) technique. Acrolein appears to be particularly valuable for immunocytochemistry, as it 1) stabilizes heterogeneous peptides and proteins rapidly and effectively, 2) retains antigenicity, and 3) preserves morphological detail.
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PMID:Acrolein: a fixative for immunocytochemical localization of peptides in the central nervous system. 618 5

In mammals, calcitonin (CT) is synthesized, stored, and secreted by intrathyroidal C cells. Several reports have suggested the presence of immunoreactive CT in the pituitary gland. We have studied the rat pituitary gland using a radioimmunoassay for CT and have also found immunoreactive CT-like material. Assay of extracts of whole rat pituitary glands was performed using a radioimmunoassay for human CT, which gave identical dilution curves with synthetic human CT (hCT), synthetic rat CT (rCT), and mouse and rat thyroid extracts, but not with a variety of other pituitary and hypothalamic peptides. Immunoreactive CT (iCT) content of extracts of whole pituitary glands ranged from 6 to 72 pg/mg wet weight of tissue (60-840 pg/whole pituitary gland), whereas iCT was not measureable (less than 5 pg/mg tissue) in similar extracts of hypothalamus and cerebral cortex. Gel filtration studies of pituitary extracts showed a peak of iCT, which eluted with 125I-rCT and diluted in parallel with rCT. To investigate whether the pituitary iCT was related to pro-opiomelanocortin, extracts of ACTH-producing AtT20/D16 cells from mice, which contain the ACTH precursor in large quantities, were examined and no iCT was found. Immunohistochemical studies of rat pituitary glands with peroxidase-antiperoxidase and immunofluorescent techniques showed positive staining for CT in cells in the pars anterior, but not in the pars intermedia of pars nervosa; this staining was not eliminated when the antiserum was absorbed with CT under conditions that completely obliterated staining of rat thyroid glands. Double staining demonstrated essentially two distinct populations of cells, one positive for CT and another positive for ACTH, with less than 1% of the cells positive for both ACTH and CT. Immunoreactive CT-like material was present in the pituitary glands of rats thyroparathyroidectomized 18 days before they were killed, but was diminished. Biosynthetic labeling in vitro of rat pituitary glands with 3H-leucine showed incorporation into prolactin; there was no incorporation into CT. No in vitro secretion of iCT by whole rat pituitary glands either basally or after high K+ stimulation was observed. We conclude that: (1) a substance that has certain immunologic and size characteristics of CT is present in minute amounts in the pituitary gland of rats; (2) this material is not a part of the ACTH precursor; and (3) positive immunohistochemical staining in pituitary glands may not be specific for authentic CT.
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PMID:Pituitary immunoreactive calcitonin-like material: lack of evidence for cross-reactivity with pro-opiomelanocortin. 619 Nov 78

The subcortical projections to the lateral dorsal nucleus (LD) of the cat thalamus were studied with retrograde transport techniques. Deposits of horseradish peroxidase (HRP) or fluorescent tracers were placed unilaterally in LD of adult cats, using electrophoretic or pressure injection techniques. Following post-injection survival periods of 1, 2 or 3 days, HRP retrogradely labeled cells were identified in sections reacted with benzidine dihydrochloride; fluorescent labeled cells were identified by fluorescent microscopy. Injections in LD result in retrogradely labeled neurons in all nuclei of the pretectal complex, including the nucleus of the optic tract (NTO), the posterior pretectal nucleus (NPP), the anterior pretectal nucleus (NPA), the pretectal olivary nucleus (NOL), and the medial pretectal nucleus (NPM). Small electrophoretic injections of HRP were used to investigate a possible topographic organization of the pretectal projections. Results from a variety of injection sites indicate only a subtle rostral-caudal gradient. That is, small injection sites in rostral LD result in retrograde labeling of neuron somata in the rostral parts of NTO, NPA and NPP, and throughout NPM. Injections in caudal LD result in labeled cells more caudally situated in NTO, NPA, NPP, and throughout NPM. Injections in the pulvinar (Pul) also result in retrogradely labeled cells in the pretectal complex, particularly NTO, NPP, and NOL. Experiments with injections of distinguishable fluorescent tracers in LD and Pul reveal that many more cells project to Pul than to LD. These experiments also reveal that while neurons that project to LD are intermingled with neurons that project to Pul, the two projections originate from separate subpopulations of cells. These results are discussed in regard to phylogenetic comparison of pretectal projections and subcortical pathways of sensory input to the limbic system.
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PMID:Projections from the pretectal complex to the thalamic lateral dorsal nucleus of the cat. 619 3

We adapted an uncommon peroxidase substrate, ortho-dianisidine, to double immunostaining methodology in order to analyze the degree of neuronal coexistence of pro-opiomelanocortin-derived peptides and to compare the distribution of neurons containing beta-endorphin immunoreactivity (ir) with those containing enkephalin-ir and dynorphin-ir in the medial basal hypothalamus. Double immunostaining demonstrated co-localization of beta-endorphin-ir, adrenocorticotropic hormone-ir, and gamma 3-melanocyte stimulating hormone-ir in medial basal hypothalamus (MBH) neurons. However, while all perikarya containing beta-endorphin-ir invariably contained adrenocorticotropic hormone-ir, not all of these cell bodies contained gamma 3-melanocyte stimulating hormone-ir. In contrast, separate neuronal cell bodies containing beta-endorphin-ir, enkephalin-ir, and dynorphin-ir were distributed throughout the rostral-caudal extent of the MBH. Fibers containing enkephalin-ir closely surrounded cell bodies containing beta-endorphin-ir, suggesting axosomatic contacts between these two opioid peptidergic neuronal populations.
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PMID:Double immunostaining reveals distinctions among opioid peptidergic neurons in the medial basal hypothalamus. 619 87

The sequential application of the peroxidase-antiperoxidase (PAP) technique with nickel-intensified DAB and with DAB alone was used to visualize black peptide-immunoreactive endings on amber serotonin-immunoreactive cells in 1-2-micron paraffin sections of the hamster medulla. Met-enkephalin- and substance P-positive terminals were present on serotonin cells in the raphe nuclei, the ventral reticular formation, and in the nucleus interfascicularis hypoglossi. The presence of enkephalin-immunoreactive endings on medullary serotonin-immunoreactive cells correlates with the analgesia and autonomic changes that result from the application of morphine or met-enkephalin to the medulla.
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PMID:Visualization of peptide-immunoreactive processes on serotonin-immunoreactive cells using two-color immunoperoxidase staining. 619 59

The organization of the projection from the pretectal region to the inferior olive in the cat was studied with autoradiographic and horseradish peroxidase (HRP) methods. After injections of HRP into the olive in six cats, cells were labeled ipsilaterally in the anterior pretectal nucleus (NPA), the posterior pretectal nucleus (NPP), the nucleus of the optic tract (NOT), and the dorsal terminal nucleus of the accessory optic tract (DTN). In three experiments, tritiated amino acids were injected into those parts of the pretectal region which contained labeled cells in the HRP experiments, and the projections to the olive were plotted. Both NPA and NPP projected to the rostral half of the dorsal accessory olive, the rostromedial margin of the ventral lamella, and the lateral part of the ventrolateral outgrowth. NOT projected to the caudal half of the dorsal cap, while DTN projected to both the dorsal cap and nucleus beta. The projections are entirely ipsilateral.
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PMID:Olivary projections from the pretectal region in the cat studied with horseradish peroxidase and tritiated amino acids axonal transport. 620 13

For simultaneous ultrastructural localization of intracellular peptides, protein A-gold techniques or immuno-gold techniques have generally been applied. The present study reports a double immunostaining procedure for simultaneous visualization of two hypophysial hormones (prolactin and corticotropin) on a single ultrathin section of the pars distalis of an amphibian. Prolactin and corticotropin antisera were respectively raised in guinea pigs and rabbits and were applied simultaneously to ultrathin sections. Antigenic binding sites were detected under the electron microscope using differently labeled species-specific secondary antisera raised in goats or sheep. Three labels (gold particles, ferritin, peroxidase) were checked for double labeling. The combinations investigated were: 1) two gold preparations or IgG-gold labeled with different-sized gold particles; 2)IgG-gold and IgG-ferritin; 3) IgG-gold and IgG-PAP (peroxidase-antiperoxidase). The double-immunostaining procedures described here have proved useful in the simultaneous ultrastructural localizations of two intracellular antigens on a single tissue section. These procedures constitute a basis for the development of triple immunostaining methods.
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PMID:A double-immunostaining procedure using colloidal gold, ferritin, and peroxidase as markers for simultaneous detection of two hypophysial hormones with the electron microscope. 620 36

The peroxidase-antiperoxidase technique has been used to study sites of pituitary hormone storage and binding. Some recent findings from our laboratory show that the technique can make intriguing contributions to our understanding of pituitary cell function. In serial, ultra-thin sections, one can identify two or three hormones in a given cell. During pre-pubertal development, gonadotropes may contain adrenocorticotropin immunoreactivity. Brain releasing hormones may be stored or sequestered in granules of cells they stimulate. This report includes a discussion and critique of our recent findings and interpretations which must be considered before one draws any conclusions about their biological significance.
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PMID:A critique of the contributions of immunoperoxidase cytochemistry to our understanding of pituitary cell function, as illustrated by our current studies of gonadotropes, corticotropes and endogenous pituitary GnRH and TRH. 625 27


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