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

The existence of possible local mediators of the inhibitory effect of neurotensin on gastric acid secretion has not been determined. We perfused rats intragastrically with warmed saline and stimulated acid secretion with intravenous pentagastrin, 32 micrograms/kg/hr, and found that anesthesia with pentobarbital resulted in marked inhibition of acid secretion by intravenous neurotensin; however, anesthesia with urethane prevented this inhibitory effect of neurotensin from occurring. In addition, we found a significant increase in somatostatin-like immunoreactivity in portal venous blood during neurotensin infusion in pentobarbital-anesthetized rats. Neither neurotensin nor pentagastrin infusion modified gastric luminal somatostatin-like immunoreactivity after either pentobarbital or urethane, and rats anesthetized with urethane did not show an increase of somatostatin-like immunoreactivity in portal venous blood during neurotensin infusion. These results suggested that somatostatin-like immunoreactivity, released into the portal circulation, was necessary for exogenous neurotensin to inhibit pentagastrin-stimulated gastric acid secretion under these conditions in anesthetized rats.
 ...
PMID:Anesthetic dependence of the inhibitory effect of neurotensin on pentagastrin-stimulated acid secretion in rats. A possible role for somatostatin. 167 Dec 92

90 primary breast carcinomas and 18 metastases were immunostained for c-erbB-2 protein and neuron specific enolase. 30 tumours were c-erbB-2 negative and NSE positive, 23 tumours were NSE negative and c-erbB-2 positive. 1 tumour expressed focal immunoreactivity for both markers. 54 of the 108 tumours (50%) did not express either marker. Hormone immunoreactivity was present in single cells and in small groups of cells in 18 of the 31 NSE positive tumours. Bombesin, neurotensin and prealbumin were present in 4 cases each, followed by beta-endorphin and VIP in 3 cases each, leu-enkephalin in 2 cases and gastrin, serotonin, substance P, glucagon and somatostatin in 1 case each. None of 10 NSE negative breast carcinomas were comprised of cells expressing immunoreactivity for hormones. By immunoelectron microscopic examination the c-erbB-2 protein was shown to be present on the cell membrane, on smooth areas, microvilli and in coated pits. Immunoreactivity was also expressed in vesicles in cytoplasm and along rough endoplasmic reticulum. The study shows that c-erbB-2 protein expression and neuroendocrine activity are present in different tumour cell populations. This supports the hypothesis that the presence of c-erbB-2 protein, indicating an elevated cellular tyrosine kinase activity with stimulation of growth, intracellular Ca++, and phosphatidylinositol derivates, means that the same cell does not need regulation of the same factors by stimulation of peptide hormone receptors. Thus the production of autocrine and paracrine factors is switched off.
 ...
PMID:C-erbB-2 protein and neuroendocrine expression in breast carcinomas. 167 29

The physiological regulation of intestinal proglucagon-derived peptide secretion has not been well studied. We have therefore used a fetal rat intestinal cell culture model to investigate the control of secretion of the gut glucagon-like immunoreactive (GLI) peptides by other intestinal regulatory peptides in vitro. Secretion of the intestinal GLI peptides was found to be stimulated in a dose-dependent fashion by the intestinal endocrine peptide, gastric inhibitory peptide (at greater than or equal to 10(-10) M, P less than 0.05), and by the neurocrine peptides, gastrin-releasing peptide (at greater than or equal to 10(-12) M, P less than 0.05), and calcitonin gene-related peptide (at greater than or equal to 10(-8) M, P less than 0.05). Gastrin-releasing peptide and its amphibian equivalent, bombesin were equipotent in stimulating GLI peptide secretion. In contrast, the endocrine and neurocrine intestinal somatostatin-related peptides, somatostatin-28 and -14, inhibited release of the GLI peptides, at concentrations of 10(-10) (P less than 0.01) and 10(-8) (P less than 0.01) M, respectively, with significant differences in potency between the two peptides detected at 10(-10) M (P less than 0.05). The inhibitory effects of both somatostatin-28 and -14 could be blocked by preincubation of the cells with pertussis toxin (P less than 0.05). Dose-dependent stimulation of gut GLI peptide secretion was also detected in response to treatment of cultured cells with sodium oleate (at 10(-4) M; P less than 0.05), or with the cholinergic agonist bethanecol (at greater than or equal to 100 microM; P less than 0.05). Other endocrine [cholecystokinin, glucagon, glucagon-like peptide-1(1-37), glucagon-like peptide-1(7-37), glucagon-like peptide-2, neurotensin, and peptide YY] and neurocrine (vasoactive intestinal peptide) peptides, and the synthetic glucocorticoid, dexamethasone, were without effect on secretion of the gut GLI peptides, at doses of 10(-12) to 10(-6) M. The results of the present study therefore demonstrate that secretion of the intestinal proglucagon-derived peptides is under the regulatory control of a wide variety of intestinal endocrine and neurocrine peptides, as well as nutrients (fats) and neurotransmitters (acetylcholine).
 ...
PMID:Regulation of intestinal proglucagon-derived peptide secretion by intestinal regulatory peptides. 167 88

In light of the effects of gastrointestinal (GI) peptides on bile secretion and biliary tract mobility, we studied the effects of GI peptides on gallstone formation in guinea pigs fed on low protein lithogenic diet. The peptides under study included cholecystokinin octapeptide (CCK-8), vasoactive intestinal peptide (VIP), somatostatin (SRIF), secretin (SEC), and neurotensin (NT). Hepatic bile flow, electrolytes, and other bile components were also measured. It was found that CCK-8 and VIP suppressed the formation of gallstones and increased hepatic bile flow and Na+, K+, Cl- output significantly. On the other hand, SRIF significantly promoted gallstone formation. The rates of gallstone formation in CCK-8, VIP, and SRIF treated guinea pigs were 15.4%, 23.5%, and 88.0%, respectively, in contrast to 56.8% in the control group. The inhibitory effect of CCK-8 and promoting effect of SRIF on gallstone formation were dose-dependent.
 ...
PMID:Effects of gastrointestinal peptides on formation of gallstone in guinea pigs. 167 24

A comparison of previous immunocytochemical studies reveals a striking similarity in the morphologies of the populations of somatostatin-like and neurotensin-like immunoreactive amacrine cells in the chicken retina. A double-label analysis was performed to determine if these two neuroactive peptides coexist in chicken amacrine cells. An examination of retinal cryosections collected throughout the retina revealed that all labelled cells express both somatostatin- and neurotensin-like immunoreactivity. Therefore, these results indicate the presence of a single population of chicken amacrine cells whose members contain both of these neuroactive peptides.
 ...
PMID:Coexistence of somatostatin and neurotensin in amacrine cells of the chicken retina. 167 4

The endocrine cells of the chicken proventriculus were investigated immunocytochemically, using the peroxidase-antiperoxidase technique on paraffin and semithin sections for light microscopy, and immunogold staining in osmium-fixed material for electron microscopy. The fixation procedure also allowed a detailed ultrastructural investigation. Twenty-three antisera were tested and 7 immunoreactive cell-types were identified: D-cells containing somatostatin-like peptide; EG-cells immunoreactive to anti-glucagon, anti-GLP1 and anti-neurotensin; NT-cells labelled only with anti-neurotensin; BN-cells containing bombesin-like material; ENK-cells showing met-enkephalin immunoreactivity; EC-cells reactive to anti-serotonin; and APP-cells positive to anti-avian pancreatic polypeptide. In addition, enterochromaffin-like (ECL) cells, were also detected by electron microscopy. The presence of ENK-cells and the ultrastructure of these and NT-cells are described for the first time in chicken proventriculus, and glucagon. GLP1 and neurotensin are shown to be colocalized in the EG-cells.
 ...
PMID:Immunocytochemical and ultrastructural characterization of endocrine cells in chicken proventriculus. 167 89

Several neuropeptides known to alter gastrointestinal motility are present in milk. We investigated the effect of gastric administration of neurotensin, bombesin, somatostatin, and vasoactive intestinal polypeptide on gastrointestinal motility in suckling rats. We gavage fed 7- to 10-day-old rats with a meal consisting of 10 microliters/g of body weight of 0.9% NaCl with 51Cr tracer and one of the peptides (0, 0.1, 10, and 1,000 ng/ml). We estimated the rates of gastric emptying and the small intestinal transit from the distribution of the radioactivity in the gut. Approximately one-half of the counts emptied from the stomach in 15 min. Both gastric emptying and small intestinal transit were time dependent and were accelerated by metoclopramide and inhibited by butylscopolamine. Neurotensin 1 micrograms/ml accelerated the gastric emptying by 35% (p less than 0.02). Small intestinal transit was also accelerated (p less than 0.05). The other neuropeptides had no effect on gastric emptying and small intestinal transit. Neurotensin did not change either the gastric emptying or small intestinal transit in weaned rats, 40-50 days old, studied in the same manner. These data suggest that the intraluminal administration of neurotensin may increase gastrointestinal motility in suckling animals.
 ...
PMID:Oral neurotensin increases gastrointestinal transit in suckling rats. 168 Oct 45

Patterns of immunoreactivity for calcium-binding protein, tyrosine hydroxylase and four neuropeptides in the ventral striatum (nucleus accumbens, olfactory tubercle and ventromedial parts of the caudate nucleus and putamen) were compared to patterns of these markers in the dorsal striatum (the majority of the neostriatum) in rhesus monkey. The striatal mosaic was delineated by calcium-binding protein and tyrosine hydroxylase immunoreactivities. Both markers were found preferentially in the matrix of the dorsal striatum. The mosaic configurations of tyrosine hydroxylase, but not calcium-binding protein immunoreactivity, were similar in dorsal and ventral striatal regions. Substance P and leucine-enkephalin were not distributed homogeneously; distinct types and the prevalence of patches of substance P and leucine-enkephalin immunoreactivity distinguish the dorsal striatum from the ventral striatum and distinguish the caudate nucleus from the putamen. In the dorsal striatum, substance P and leucine-enkephalin patches consist of dense islands of immunoreactive neurons and puncta or clusters of immunoreactive neurons marginated by a dense rim of terminal-like puncta; the matrix was also enriched in leucine-enkephalin-immunoreactive neurons but contained less substance P-immunoreactive neurons. Patches were more prominent in the caudate nucleus than in the putamen. In the caudate, compartments low in tyrosine hydroxylase and calcium-binding protein immunoreactivities corresponded to cytologically identified cell islands and to patches enriched in substance P and leucine-enkephalin. These patches had a discrete infrastructure based on the location of substance P and leucine-enkephalin-immunoreactive neurons and terminals. In the ventral striatum, patches that showed low levels of substance P and leucine-enkephalin immunoreactivities were embedded in a matrix rich in immunoreactive cell bodies, fibers and terminals. In the accumbens, regions showing little tyrosine hydroxylase were in spatial register with patches low in substance P and leucine-enkephalin. Neurotensin- and somatostatin-immunoreactive neurons or processes were also compartmentally organized, particularly in the ventral striatum. Neurotensin-immunoreactive neurons were present predominantly in the nucleus accumbens but not in the dorsal striatum. Some regions enriched in neurotensin immunoreactivity were spatially registered with zones low in tyrosine hydroxylase, substance P and zones enriched in leucine-enkephalin. Areas enriched in somatostatin-immunoreactive processes overlapped with both tyrosine hydroxylase-rich and -poor regions in the ventral striatum. Our results show that the chemoarchitectonic topography of the striatal mosaic is different in the dorsal and ventral striatum of rhesus monkey and that the compartmental organization of some neurotransmitters/neuropeptides in the ventral striatum is variable and not as easily divisible into conventional patch and matrix regions as in the dorsal striatum.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:The striatal mosaic in primates: patterns of neuropeptide immunoreactivity differentiate the ventral striatum from the dorsal striatum. 168 64

By means of double immunolabeling procedures it has been possible to demonstrate glucocorticoid receptor (GR) immunoreactivity (IR) in large numbers of various peptidergic neurons of the brain including neurons containing gastrointestinal peptides, opioid peptides, and peptides with a hypothalamic hormone function. For each peptide system, however, marked heterogeneities exist among brain regions. Thus, in the neocortex and the hippocampal formation most of the brain peptide neurons lack GR IR, while the same types of peptide neurons in the arcuate and paraventricular nucleus [e.g. neuropeptide Y (NPY), somatostatin (SRIF) and the cholecystokinin (CCK) neurons] possess strong GR IR. Furthermore, in the arcuate, parvocellular part of the paraventricular nuclei and the central amygdaloid nucleus practically all the peptidergic neurons are strongly GR IR, while in the lateral hypothalamus, mainly the neurotensin (NT) and galanin (GAL) IR neurons are GR IR. These marked differences among areas probably reflect functional differences dependent upon their participation in stress regulated circuits. All the paraventricular NT, corticotropin-releasing factor (CRF), growth hormone-releasing factor (GRF), thyrotropin-releasing hormone (TRH) and SRIF IR neurons appear to contain GR IR, while the luteinizing hormone-releasing hormone (LHRH) IR neurons lack GR IR, underlying the importance of glucocorticoids (GC) in controlling endocrine function. Finally, the GC may influence pain and mood control mainly via effects on enkephalin (ENK) neurons especially in the basal ganglia (mood) and on all beta-endorphin (beta-END) neurons of the arcuate nucleus, while most of the dynorphin neurons are not directly controlled by GC.
 ...
PMID:Central peptidergic neurons as targets for glucocorticoid action. Evidence for the presence of glucocorticoid receptor immunoreactivity in various types of classes of peptidergic neurons. 168 65

Endocrine cells in the gastrointestinal tract of the domestic duck were identified immunocytochemically using antisera specific to bombesin, chromogranin A, cholecystokinin (CCK), gastrin, glucagon, neuron specific enolase (NSE), neurotensin, secretin, 5-hydroxytryptamine (5-HT), somatostatin, substance P and vasoactive intestinal polypeptide (VIP). Chromogranin A, 5-HT and somatostatin immunoreactive cells were widespread throughout the gastrointestinal tract. Bombesin immunoreactive cells were observed only in the proventriculus and the gizzard. CCK, substance P and neurotensin immunoreactive cells were present in the intestinal tracts from the duodenum to the colorectum. The latter were numerous also in the antrum. Gastrin cells were peculiar to the antrum but present also in the gizzard and small intestine. Glucagon immunoreactive cells were present in the jejunum-ileum and above all in the large intestine. Only few secretin cells were present in the duodenum. The highest frequency of endocrine cells was found in the antrum, while the lowest was observed in the caeca. Antisera to somatostatin and substance P showed numerous nerve cells and fibers besides endocrine cells, whereas NSE and VIP immunopositivity was found in the nervous structures only of the gut wall.
 ...
PMID:An immunohistochemical study on the endocrine cells in the gastrointestinal tract of domestic duck. 168 96


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>