Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Norepinephrine, acetylcholine, and certain peptides are contained in mucosal nerves and have potent effects on transepithelial water and electrolyte fluxes. It is difficult to ascribe roles for these nerves as their sources are unknown. The present studies were undertaken to determine the origins of nerve fibers that are found in the mucosa of the guinea pig small intestine and which contain one of the following substances: vasoactive intestinal peptide, substance P, somatostatin, neuropeptide Y, cholecystokinin, or norepinephrine. Nerve fiber origins were ascertained by making lesions to sever pathways through which the nerves could reach the mucosa. The lesioning operations were homotopic autotransplants of short (2 cm) segments of intestine; myectomies, in which a 5-10-mm length of intestine was stripped of longitudinal muscle and myenteric plexus; and extrinsic denervation, in which nerves reaching the intestine through the mesentery were severed. The results of these studies, considered along with previously published work, led to the upcoming conclusions. Nerve fibers in the mucosa showing immunoreactivity for vasoactive intestinal peptide, somatostatin, cholecystokinin, and neuropeptide Y arise from cell bodies in the overlying submucous plexus. Substance P fibers arise in part from the overlying submucous plexus and in part from the overlying myenteric plexus. Mucosal norepinephrine fibers arise from extrinsic sympathetic ganglia. Enkephalin, gastrin-releasing peptide, and 5-hydroxytryptamine, which are in some enteric nerves, are not found in submucous nerve cells and few, if any, fibers containing these substances supply the mucosa. Thus, the mucosa receives a dense nerve supply, much of which arises locally from submucous ganglia.
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PMID:Origins of peptide and norepinephrine nerves in the mucosa of the guinea pig small intestine. 619 54

The peptides, neurotensin, substance P, somatostatin, and bombesin, several analogues and fragments of neurotensin and compound 48/80, all caused the secretion of both endogenous 5-hydroxytryptamine (5-HT) and histamine. There was no differential effect of any of the secretagogues tested on the secretion of 5-HT and histamine. Amitriptyline prevented the secretion of histamine in response to stimulation by neurotensin, substance P, somatostatin or compound 48/80 but was without effect on the secretion of endogenous 5-HT.
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PMID:Parallel secretion of endogenous 5-hydroxytryptamine and histamine from mast cells stimulated by vasoactive peptides and compound 48/80. 620 Jan 70

A tumor substrain secreting a large amount of serotonin [5-hydroxytryptamine (5-HT); CAS: 50-67-9; 3-(2-amino-ethyl)indol-5-ol] and a minute amount of histamine (CAS: 51-45-6) has been isolated from the previously established strain of transplantable gastric carcinoid of Mastomys (Praomys) natalensis secreting both histamine and 5-HT. Mastomys bearing a large growing transplant and excreting a large amount of 5-hydroxy-indoleacetic acid [(5-HIAA) CAS: 54-16-0] were associated often with reddening of the nose, lower lip, auricles, hands, and feet. Soon after the animals were anesthetized by ether or other volatile anesthetics, the tinges of red of the above-mentioned exposed parts abruptly turned bright red and rapidly spread over the neck, upper chest, and epigastric area. The reddening was transient, lasting 1.5-5 minutes, thereby fulfilling the criteria of flushing. The severity of ether-provoked flushing in tumor-bearing Mastomys paralleled the urinary excretion levels of 5-HIAA. The ether-provoked flushing was prevented completely by sc injection of either ketanserin (150 micrograms) or somatostatin (20 micrograms). The same ether-provoked flushing as found in tumor-bearing Mastomys could be reproduced in normal ones by constant infusion of 20 mg 5-HT/kg/24 hours (i.e., doses comparable to those released from a transplanted tumor) through an osmotic minipump implanted subcutaneously.
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PMID:Novel flushing provoked by volatile anesthetics in Mastomys natalensis bearing a transplantable substrain of gastric carcinoid that predominantly secretes serotonin. 620 24

Effects of neuroactive peptides on the release of labeled 5-hydroxytryptamine (5-HT) from preloaded rat spinal cord slices were investigated. The 5-HT release was significantly stimulated by somatostatin (10-50 microM) and substance P (10-50 microM), but not by neurotensin (50 microM), beta-endorphin (30 microM) and methionine-enkephalin (met-enk) (100 microM). Somatostatin-stimulated 5-HT release was markedly inhibited by gamma-aminobutyric acid (GABA) (30 microM), but not by baclofen (30 microM) and met-enk (100 microM). Substance P-stimulated 5-HT release was strongly inhibited by GABA (30 microM) and baclofen (30 microM), but not by met-enk (100 microM). High concentrations (20 mM) of potassium also stimulated 5-HT release. The high potassium-stimulated 5-HT release was not affected by GABA (30 microM) and met-enk (100 microM). These results suggested further evidence on the important role of somatostatin and substance P as modulators of serotonergic neurones.
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PMID:Effect of neuroactive peptides on labeled 5-hydroxytryptamine release from rat spinal slices in vitro. 620 42

3-Mercaptopropionic acid (3MP) (1 mM) inhibited the potassium-evoked release of endogenous GABA from slices of rat hippocampus and cerebral cortex in vitro. This did not appear to be due to an inhibition of GABA biosynthesis, since 3MP failed to affect the basal rate of GABA release or to accelerate the decline in the GABA content of tissue slices during prolonged exposure to 3MP (up to 120 min). 3MP, furthermore, inhibited the potassium-evoked release of [3H]GABA from preloaded brain slices, suggesting a direct inhibitory effect on GABA release. The threshold concentration was approximately 0.1 mM. 3MP at 1 mM failed to inhibit the potassium-evoked release of [3H]5-hydroxytryptamine, [3H]noradrenaline or somatostatin under similar conditions. The ability of 3MP to inhibit GABA release may contribute to the convulsant properties of this substance in vivo.
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PMID:3-mercaptopropionic acid inhibits GABA release from rat brain slices in vitro. 627 39

Drug addicts abusing heroin substitutes contaminated with N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and perhaps those who work with this substance, may develop symptoms similar to those seen in Parkinson's disease [7, 12, 13]. We describe the results of a study in which rats were given daily injections of MPTP for two weeks. A progressive suppression of activity was seen, but the subjects rapidly recovered when treatment ceased. The animals were then injected with D-amphetamine or apomorphine; the former drug enhanced activity, to levels seen in control (non-MPTP treated) subjects. Apomorphine had no effect, either on control or MPTP-treated subjects. The effects of acute (0, 2.5, 5.0 and 10.0 mg per rat) administration of MPTP were also studied. The two lower doses significantly decreased activity, but the highest dose did not. Histological examination showed that 2 weeks' treatment with MPTP did not produce neuronal degeneration in the pars compacta of the substantia nigra (SN). In these animals, there were no changes in levels of dopamine, 5-hydroxytryptamine, or their metabolites in either the SN or the caudate nucleus. MPTP had no effect on the levels of neurotensin, somatostatin and substance P in several brain areas. It is concluded that MPTP has reliable effects on locomotor activity in rats without producing measurable histological or neurochemical changes in the nigrostriatal dopaminergic system.
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PMID:N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) affects locomotor activity without producing a nigrostriatal lesion in the rat. 633 3

The presence of peptides and 5-hydroxytryptamine (5-HT) in neurons and endocrine cells in the gastrointestinal tract of the spiny dogfish, Squalus acanthias, was investigated by means of immunohistochemistry, and the distribution of catecholamines by use of the Falck-Hillarp fluorescence-histochemical technique. Bombesin-like immunoreactivity was present in numerous nerves in all layers and all parts of the gut, and also in endocrine cells in the mucosa throughout the stomach, rectum and intestine. VIP-like immunoreactivity occurred in an abundance of nerve fibres and in nerve cell bodies in all parts of the gut except the oesophagus, while 5-HT-like immunoreactivity was found sparsely in nerve fibres and more frequently in endocrine cells throughout the gut. Gastrin/CCK-like immunoreactivity was present in numerous nerve fibres in the rectum, but only in scattered fibres in the other parts of the gut. Endocrine cells showing gastrin/CCK-like immunoreactivity were present in the intestine only. Somatostatin-like immunoreactivity occurred in both nerve fibres and endocrine cells of the stomach and intestine, but only in nerves in the rectum. Neurotensin-like immunoreactivity was confined to endocrine cells of the intestine. Falck-Hillarp fluorescence histochemistry revealed 5-HT in endocrine cells and catecholamines in nerve fibres (and possibly also in endocrine cells) throughout the gut. Bombesin-, VIP-, gastrin/CCK- and somatostatin-like immunoreactivities and catecholamine fluorescence were present in nerve fibres of the rectal gland and, with the exception of gastrin/CCK-like immunoreactivity, also in nerve bundles in the walls of the coeliac and mesenteric arteries. The findings of the present study form an anatomical basis for the assumption that several of the neuropeptides and amines could function as neurotransmitters or neuromodulators in the gut of Squalus.
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PMID:Bombesin-, gastrin/CCK-, 5-hydroxytryptamine-, neurotensin-, somatostatin-, and VIP-like immunoreactivity and catecholamine fluorescence in the gut of the elasmobranch, Squalus acanthias. 636 87

Nine cases of endocrine carcinoma, intermediate-cell type of the uterine cervix, were found in a study of 404 cases listed in the files of the University of Texas M. D. Anderson Hospital and Tumor Institute at Houston as adenocarcinoma of the cervix. Based on light microscopic patterns, these cases were divided into pure endocrine carcinoma (six cases), and endocrine carcinoma mixed with adenocarcinoma (three cases). All tumors were 3 cm or larger in at least one dimension. On light microscopic examination, the predominant pattern was trabecular; however, insular, glandular, and spindle patterns were also identified. Argyrophilic granules were demonstrated in all cases by Grimelius stain, and Fontana-Masson (argentaffin) stain was negative. Electron microscopic examination of three cases showed membrane-bound, dense-core granules of the neurosecretory type. Although no endocrine symptoms were found, immunoperoxidase studies demonstrated 5-hydroxytryptamine in seven cases, substance P in three, vasointestinal polypeptide in two, pancreatic polypeptide in one, and somatostatin in one. Clinical behavior of these tumors was extremely aggressive. Although five cases were Stage IB at presentation, two Stage IIB, one Stage IIIB, and one Stage IV, 87.5% of these patients died of their neoplasms within 3 years. This study emphasizes the importance of correctly diagnosing endocrine carcinoma, intermediate-cell type in the uterine cervix, because of the poor prognosis of this tumor when compared with adenocarcinoma of the cervix.
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PMID:Endocrine carcinoma intermediate cell type of the uterine cervix. 638 96

Goblet-cell carcinoids are particular mucus-producing tumors combining features of typical carcinoids and adenocarcinomas. The immunoreactivity of five goblet-cell carcinoids of the appendix and one tumor of the ileum for 5-hydroxytryptamine (5-HT, serotonin), glucagon, somatostatin, substance P (SP), neuron-specific enolase (NSE), lysozyme, secretory component (SC) and carcino-embryonic antigen (CEA) was compared with that of the mucosa of the appendix (n = 24) and ileum (n = 12), and of typical carcinoids (appendix: n = 10; ileum: n = 3). The goblet-cell carcinoids were consistently lysozyme-, SC- and CEA-reactive and contained weakly NSE reactive endocrine cells, while typical carcinoids were lysozyme-, SC- and CEA-negative, but strongly NSE- reactive. Two goblet-cell carcinoids were glucagon-reactive, one displayed SP-reactivity, one malignant tumor was reactive to the alpha-chain of glycoprotein hormones; six of ten typical appendix carcinoids were SP reactive, as were the three typical ileum carcinoids. Using the immunogold technique combined with the alcian-blue reaction, the presence of 5-hydroxytryptamine (5-HT) and mucus was demonstrated within the same cell. These findings suggest histogenetic differences between goblet-cell carcinoids and typical carcinoids; the former are possibly derived from undifferentiated stem cells, whereas the latter probably arise from endocrine cells in the mucosal stroma.
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PMID:Combined production of mucus, amines and peptides by goblet-cell carcinoids of the appendix and ileum. 648 83

Several ion channels can be regulated by G proteins in a "membrane-delimited" manner. The cardiac muscarinic K+ (KACh) channel, which is responsible for the acetylcholine (ACh) or adenosine-induced deceleration of heart beat and atrioventricular conduction, is the prototype of this type of receptor-dependent regulation of ion channels. Because similar transduction mechanisms are utilized by various membrane receptors, such as somatostatin, 5-hydroxytryptamine-1, alpha 2-adrenergic, mu-and delta-opioid, D2-dopamine, and gamma-aminobutyric acid B receptors, in neuronal, hormone-secreting, renal, or smooth muscle cells, the G protein (GK)-KACh channel system illustrates the principles underlying one of the most important cell signaling mechanisms (B. Hille. Neuron 9: 187-195, 1992). It seems that both alpha- and beta gamma-subunits of GK may be involved in the regulation of the KACh channel of mammalian atrial muscle. A general consensus of opinion has emerged, after some years of controversy, to support the notion that physiological activation of the channel by GK is the responsibility of the beta gamma-subunits. Recent evidence suggests that the KACh channel interacts with the alpha-subunit in the terminating process of activation.
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PMID:G protein regulation of cardiac muscarinic potassium channel. 748 49


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