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

Eighty-one primary ovarian carcinoids and intraovarian metastases from six mid-gut carcinoids were examined for the presence of tumor cells immunoreactive with antisera raised against various neurohormonal peptides, mostly of gastroenteropancreatic (GEP) origin. Twenty of the primary and two of the metastatic carcinoids contained such tumor cells. The incidence of tumors with any kind of neurohormonal peptide immunoreactive tumor cells was 53% in the trabecular carcinoids, and 42% in the strumal carcinoids, whereas the incidence was much lower (7%) in the insular type. Immunoreactive pancreatic polypeptide (PP), glucagon, enkephalin, and somatostatin were those neurohormonal peptides most commonly observed in the tumor cells of the primary carcinoids. Those less commonly found were substance P, calcitonin, VIP, neurotensin, beta-endorphin, and ACTH. Four metastatic carcinoids were nonreactive with all the antisera used. Cells storing immunoreactive insulin, glucagon, PP, VIP, gastrin, substance P, or enkephalin were found in one of the two remaining metastatic carcinoids; in the other only gastrin-immunoreactive tumor cells were observed. The occurrence and distribution of tumor cells storing the neurohormonal peptides in ovarian carcinoids are discussed in relation to their possible origin in the ovary and to carcinoids in the gut.
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PMID:Neurohormonal peptides in ovarian carcinoids: an immunohistochemical study of 81 primary carcinoids and of intraovarian metastases from six mid-gut carcinoids. 611 50

The effect of VIP on prolactin secretion from incubated rat hemipituitaries was characterized. Under these conditions, the secretion of GH, LH, FSH, ACTH was not affected, indicating that the effect of VIP is hormone specific. The stimulation of prolactin was dose-dependent, with an apparent affinity of VIP of 10.9 +/- 3.1 nM and a maximal stimulation of 57.7 +/- 4.2%. Secretin, a structurally related peptide, was also active at higher concentrations, whereas another partial analogue, glucagon, was ineffective. Furthermore, VIP does not act through pituitary DA receptors since alpha-flupentixol, a potent dopaminergic antagonist, does not block the stimulation of prolactin secretion by VIP. In addition, stimulation by VIP and TRH was additive. Naloxone and met-enkephalin were ineffective on the VIP effect on prolactin release. In contrast, SRIF seems to inhibit the VIP stimulation of prolactin release. Our data suggest that VIP, which was found in the hypothalamo-hypophyseal blood at concentrations of the same order of magnitude as that found to stimulate PRL in vitro, could be a physiological PRF.
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PMID:[PRF activity of VIP in vitro (author's transl)]. 612 34

The present report concerns the immunocytochemistry of various peptide hormones and in particular their location in nervous structures. However, since the hormones observed in the neuroadenohypophysis and the digestive tractus have been examined elsewhere, they have been excluded from this study, except when considered outside there precise areas. The immunocytology of the following neuropeptides is presented, especially the particular details related to their demonstration: 1) The hypothalamic hypophysiotropic factor: LH-RF, SRIF, TSH-RF; derivatives from the so-called proopiocortine found by Mains and Eipper (1977), namely beta-LPH, enkephalins, endorphins, alpha-MSH- and ACTH-like antigens; 2) Prolactin and somathormone found outside the pituitary; 3) Gastro-intestinal hormones and their location outside the digestive hormones and their location outside the digestive mucosa, namely VIP, CCK, substance P; 4) Angiotensin II in nervous structures; 5) Neurotensin; 6) Thyrocalcitonin; 7) Relaxin, and the problem of its presence in the adult male genital tract. New data in invertebrate located vertebrate neuropeptides-like antigens in the nervous structures of pro-chordates (Ascidians) insects, crustaceans, annelids. These last findings underline the extensive significance of such hormonal molecules previously considered to be specific for vertebrates.
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PMID:Immunocytochemistry of polypeptide hormones: a review. 616 60

There are now about twelve substances, many of them peptides, that are thought to act as neurotransmitters in the enteric nervous system. Most of the studies of peptides have relied on immunochemical methods for their detection. However, difficulties arise in these studies because of the close similarities between peptides. Related peptides can be grouped in several ways according to similarities of origin, function, effects in bioassays and amino acid sequences. Peptides with the same function in different species, and only slight differences in amino acid sequence, have been called isopeptides. Peptide families that have sequences of amino acids in common, but do not necessarily have similar functions are described. In the guinea-pig small intestine, used as a model, the concentrations of fourteen nerve-related peptides and amines are compared. The actual chemical natures of the peptides are discussed. It is concluded that nerves containing authentic leu- and met-enkephelin, somatostatin and substance P are present. VIP in guinea-pig enteric nerves is different from the porcine standard. Peptides similar to authentic CCK8 and amphibian skin bombesin are present. Angiotensin and neurotensin-like peptides shown immunohistochemically are not the authentic peptides. In the longitudinal muscle plus myenteric plexus, most neuropeptide concentrations are in the range of 10-500 pmole/g. The exception is met-enkephalin (1,300 pmole/g). The amine transmitters have considerably higher concentrations, noradrenaline having a concentration of about 3,500 pmole/g and acetylcholine 1-2 x 10(5) pmole/g.
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PMID:Detection and characterisation of neurotransmitters, particularly peptides, in the gastrointestinal tract. 617 12

VIP-, substance P- and met-enkephalin-containing innervation of the human gastroduodenal mucosa and Brunner's glands was studied by immunocytochemistry on whole mount tissue preparations. A dense VIP-containing nerve supply was found around fundic and pyloric glands, while the few and scattered substance P-immunoreactive fibres tended to run across the full thickness of the gastric mucosa. In the duodenum, both VIP and substance P were present in a striking nerve network in the villi as well as in the muscularis mucosae and around blood vessels. Both peptides were also immunostained in nerve bundles and neuronal perikarya between the lobules of Brunner's glands, while only very few fibres reached the proximity of acinar cells. Met-enkephalin-immunoreactivity was detected in a small number of nerve fibres, virtually confined to the basal parts of the mucosa and to the duodenal submucous plexus.
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PMID:VIP-, substance P- and met-enkephalin-immunoreactive innervation of the human gastroduodenal mucosa and Brunner's glands. 620 42

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

A variety of neuropeptides, such as TRH, somatostatin, VIP, Substance P, neurotensin, CCK, gastrin, and opioid peptides, alter secretion of GH and PRL from the pituitary. These actions differ according to the route of administration or with experimental conditions, especially anesthesia. Among these peptides, the most consistent results have been obtained with opioid peptides, which stimulate GH and PRL release. Both beta-endorphin and enkephalins are capable of stimulating GH and PRL release in anesthetized and unanesthetized, freely moving rats. The effect is blocked by naloxone, an opiate receptor antagonist. GH secretion induced by opioid peptides seems to be mediated by an alpha-adrenergic mechanism, since treatment with DDC and fusaric acid, which are dopamine-beta-hydroxylase inhibitors, reserpine, and phenoxybenzamine which is an alpha-adrenergic blocking agent, blunted GH secretion. However, pimozide, a dopamine receptor antagonist, and propranolol, a beta-adrenergic blocking agent, were without effect. On the other hand, basal PRL secretion was augmented by pimozide, suggesting the possible involvement of dopamine. It is also possible that serotonin is involved in the GH and PRL release induced by opioid peptides. The physiological significance of opioid peptides in regulating GH and PRL secretion is still unclear. Contradictory results (12,25) have been obtained concerning the effect of naloxone on basal or stimulated GH and PRL secretion in rats, monkeys and humans when tested by the continuous blood sampling method, which rules out the erroneous evaluation of results caused by episodicity of plasma hormone levels. Further studies should clarify the physiological role of opioid peptides in regulating pituitary function.
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PMID:Effect of CNS peptides on hypothalamic regulation of pituitary secretion. 701 Sep 47

Two peptides known for their hypnogenic properties, CLIP (corticotropin-like intermediate lobe peptide or ACTH 18-39) or VIP (vasoactive intestinal polypeptide), were injected locally into the nucleus raphe dorsalis (nRD) of rats pretreated with p-chlorophenylalanine (PCPA). During the dark period, the PCPA insomnia was primarily associated with a reduction in paradoxical sleep (PS), whereas both slow wave sleep (SWS) and PS were decreased during the light period. Immunohistochemistry of serotonin in PCPA-pretreated animals indicated a clear disappearance of 5-HT fibers in the basal hypothalamus and the nRD as compared to control animals. Local injections of CLIP or VIP in the nRD restored PS and SWS. The positive injection sites corresponded to the anatomical distribution of either CLIP or VIP fibers, i.e., the entire nRD for VIP and the antero-dorsal part of this nucleus for CLIP. The sleep effects obtained in PCPA-pretreated rats involve a non-5-HT sleep permissive component within the nRD upon which these injected peptides act.
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PMID:Sleep permissive components within the dorsal raphe nucleus in the rat. 758 81

Calcitonin (CT) is a polypeptide hormone produced in the thyroid gland that regulates, blood calcium levels and bone calcium metabolism. The unexpected finding of binding sites for calcitonin in several areas of the brain oriented attention to activities of CT in the central nervous system and also to its antinociceptive action. The first report of this last effect was in 1975, and the many different experimental and clinical data on this topic reported since then are reviewed here. The heterogenous findings have been organized according to the logical classification of animal and human studies. For each of these headings, subheadings such as acute and chronic pain, different kinds of administration and different procedures used to record the results, are considered. The several proposed mechanisms of action, involving serotoninergic, catecholaminergic, Ca2+ fluxes, protein phosphorylation, beta-endorphin production, cyclooxygenase inhibition and histamine interference are also reviewed. Calcitonin, neurotensin, substance P, VIP and, recently, CGRP are some of the non-opioid peptides that have been reported to interfere with pain and that open up a new, alternative way of investigating antinociceptive drugs different than opioid or opioid-like agents. An examination of the state-of-investigation of calcitonin's antinociceptive activity in the last 17 years shows that many experimental studies indicate the existence of this effect, including studies in humans, and this opens up perspectives for therapy with a new class of antinociceptive agents.
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PMID:Calcitonin and its antinociceptive activity: animal and human investigations 1975-1992. 794 19

Endocrine cells have been identified in the intestine of the frog Rana temporaria after application of the Grimelius and Masson-Fontana techniques. These endocrine cells were examined using immunocytochemical techniques on paraffin and semithin sections for light microscopy. After testing 19 antisera, 12 immunoreactivities were identified. Numerous serotonin-, somatostatin- and GLP-1-immunoreactive cells; a moderate number of PYY-, glucagon-, VIP-, gastrin/CCK-immunoreactive cells and few human PP-, bombesin-, substance P- and neurotensin-immunoreactive cells were found. VIP- and met-enkephalin were identified in nerve fibers of the muscular layer. Using semithin-thin sections five types of endocrine cells (serotonin-, somatostatin-, gastrin/CCK-, glucagon- and bombesin-immunoreactive cells) have been characterized according to their immunocytochemical reaction and the ultrastructure of the secretory granules.
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PMID:Immunocytochemical and ultrastructural characterization of endocrine cells and nerves in the intestine of Rana temporaria. 810 59


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