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)

Up to seven endocrine cell types have been identified ultrastructurally in the pancreas, including glucagon A cells, insulin B cells, somatostatin D cells, pancreatic peptide F cells and 5-hydroxytryptamine EC cells. In addition, D1 cells, which have been proposed as the cell type producing VIP and possible P cells of unknown function are seen. Various patterns of endocrine cell differentiation have been found in 20 endocrine pancreatic tumours. Well and poorly differentiated B cells have been identified in 6 insulinomas, diagnostic G cells in 3 out of 7 gastrinomas, D1 and/or F cells in 7 diarrheogenic tumours. Moreover, cells apparently unrelated to the prevalent clinical syndrome have been noted in 8 of the 20 tumours. Granular non diagnostic cells (poorly diagnostic gastrin cells? D1 cells?) were particularly frequent in gastrinomas; agranular or poorly granular cells, either by "active" or "Stem cell" type, were present in nearly all tumours, particularly in diarrheogenic tumours, gastrinomas and malignant insulinomas. A cytological classification of pancreatic endocrine tumours is proposed.
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PMID:The endocrine cells of the pancreas and related tumours. Ultrastructural study and classification. 19 45

At least four types of endocrine-like cells have been detected histochemically in the mucosa of the human colon and rectum, i.e. argentaffin cells storing 5-hydroxytryptamine (5HT) and non-argentaffin cells reacting with glucagon, somatostatin and bovine pancreatic peptide (BPP) antibodies. Ultrastructurally, four main types and three rare types of endocrine-like cells have been identified. Among the former cells were: (1) argentaffin EC1 cells, known to store 5HT and substance P, (2) poorly argyrophil L cells, corresponding to the glucagon-immunoreactive cells storing enteroglucagon or glucagon-like immunoreactivity (GLl), (3) inconstantly argyrophil F-like cells, possibly corresponding to BPP-immunoreactive cells, and (4) fairly argyrophil H cells of unknown function. Rare D cells, corresponding to somatostatin cells, N cells, corresponding to neurotensin cells, and P cells, of unknown function, have been also found.
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PMID:Types of endocrine cells in the human colon and rectum. 69 14

Immunocytochemical localization of 5-hydroxytryptamine (5-HT) in the nervous system and aggregate tissue cultures was performed employing an antibody to 6-OH-1,2,3,4-tetrahydro-beta-carboline. A number of immunochemical and biochemical tests with the antigen and the antibody and some procedural changes in the methodology applied for immunolocalization revealed the anti-5-HT-like affinity of the antibody, if applied in paraformaldehyde-fixed tissues. Studies in the hypothalamus, striatum, brainstem, spinal cord, and pineal gland show the complexities of the serotoninergic system. Ultrastructural immunocytochemistry with the preembedding technique reveals that 5-HT synapses are of the asymmetric type. The presynaptic element contains clear, round, small vesicles, with some large dense-core vesicles. The contacts are made with the somata and primary, secondary dendrites or with spines of non-5-HT neurons. Presynaptic dendrites are found in the n. raphe dorsalis, contacting non-5-HT dendrites. Double immunocytochemical methods demonstrated contacts of 5-HT fibers on enkephalin containing neurons of the spinal trigeminal nucleus and on somatostatin containing neurons of the medullary reticular formation. In vitro studies of cultured mesencephalic neurons were performed with the method of aggregating cultures. Such development of a miniature organized nerve tissue was followed up to 35 d in culture. Organization of the neuropil and synaptogenesis was studied using standard electron microscopy. The differentiation of neurons and astrocytes was studied using antibodies to 5-HT and GFAP. Serotonin immunoreactivity could be observed in neuronal bodies and processes at light microscope level as early as the fourth day of culture.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antibodies as molecular probes in neurobiology. Identification of chemically defined neurons and synapses in tissues and tissue cultures. 128 32

The aim of this study is to describe the presence of neuroendocrine (NE) cells (paraneurons), producing biogenic amines and/or peptidergic hormones, in the female urethra of cattle, sheep, pigs, and horses, by means of histochemical and double labeling immunofluorescent techniques. 5-Hydroxy-tryptamine-, chromogranin A-, cholecystokinin- and somatostatin-containing NE cells are present in the urethral epithelium of all the species studied, with the unique exception of the lack of somatostatin cells in the horse. Paraneurons containing 5-hydroxytryptamine colocalized with chromogranin A or cholecystokinin were also found in all subjects. Such active substances are hypothesized to play a role in the contraction of the urethral musculature, emission of urogenital fluids, and inhibition of endocrine and exocrine secretions.
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PMID:Immunocytochemistry of paraneurons in the female urethra of the horse, cattle, sheep, and pig. 135 70

The cellular composition and relative frequency of the occurrence of pancreatic endocrine cells were studied immunohistochemically in a primitive eutherian and arboreal folivore, the three-toed sloth, since previous histochemical and ultrastructural studies on the endocrine pancreas of the sloth have detected only a single islet cell type, the A cell. In the sloth pancreas, four types of endocrine cells immunoreactive for glucagon, insulin, somatostatin and serotonin (5-hydroxytryptamine) were found as reported in the pancreas of human and common experimental mammals, but pancreatic polypeptide-immunoreactive cells were not detected by either avian- or bovine-pancreatic polypeptide antiserum. The endocrine cells were distributed mainly in the islets and partly also in the exocrine tissue including the pancreatic ducts. Larger or smaller clusters consisting of glucagon- and insulin-immunoreactive cells were also found frequently in the interlobular connective tissue. In the islets, glucagon- and insulin-immunoreactive cells were the most prominent cell type, while somatostatin- and serotonin-immunoreactive cells were sparse. The most striking feature in the sloth pancreas is the high frequency of glucagon-immunoreactive cells, because these cells are by far less in number than insulin-immunoreactive cells in the islets of human and common experimental mammals. This appears to be an intriguing characteristic of the sloth pancreas in a possible relation to the animal's unique metabolic system and the phylogenetical position.
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PMID:An immunohistochemical study on the pancreatic endocrine cells of the three-toed sloth, Bradypus variegatus. 135 79

1. A study was made of the pelvic and the splanchnic nerve supplies to the toad large intestine. 2. Stimulation of pelvic nerve fibres in the 9th and 10th spinal nerves caused a series of contractions of the circular muscle, only the first of which was abolished by hyoscine. The entire response was blocked by d-tubocurarine. The response was not affected by capsaicin treatment. 3. Stimulation of the splanchnic nerves caused a rapid contraction followed by a prolonged relaxation. The relaxation was abolished by bretylium. The contraction was selectively antagonised by prolonged exposure to capsaicin. Splanchnic nerve stimulation also caused a slow, prolonged excitation that was abolished by bretylium. 4. Application of adrenaline caused relaxation of circularly cut strips of large intestinal wall, whereas substance P, acetylcholine, 5-hydroxytryptamine, somatostatin and galanin caused contraction. 5. The results suggest that stimulation of the pelvic nerves releases acetylcholine and a non-cholinergic co-transmitter from peripheral postganglionic neurons. Both the inhibitory response to splanchnic nerve stimulation and the subsequent slow excitation appear to be mediated by adrenergic nerves. The rapid capsaicin-sensitive excitation is likely to be due to release of substance P from antidromically activated afferent nerve fibres in the splanchnic outflow.
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PMID:The autonomic innervation of the large intestine of the toad (Bufo marinus). 135 34

Several lines of evidence suggest that somatostatin (SS) may interact with serotonergic neurons in the central nervous system. To assess whether SS acts presynaptically on serotonin (5-hydroxytryptamine, (5-HT)) neurons, SS receptors were measured in membranes from the hippocampus, a brain region that receives dense serotonergic innervation and has a high number of SS receptors in control and 5,7-dihydroxytryptamine (5,7-DHT)-treated rats, at 1 and 3 weeks after injection. Intracerebroventricular (i.c.v.) injection of the 5-HT-specific neurotoxin 5,7-DHT (11 micrograms (free base) dissolved in 10 microliters of isotonic saline containing 0.01% ascorbic acid) produced a 70% reduction in hippocampal 5-HT content at 3 weeks after injection but not at 1 week. This change was associated with a significant decrease in SS receptor density in rat hippocampus only at 3 weeks following the injection, without influencing the apparent affinity of the receptors at any time. Administration of 5,7-DHT did not affect somatostatin-like immunoreactivity (SSLI) levels at both times studied. These results suggest that some of the hippocampal SS receptors may be localized presynaptically on the serotonergic nerve terminals.
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PMID:Reduction of somatostatin receptors in rat hippocampus by treatment with 5,7-dihydroxytryptamine. 136 78

A possible role for neuropeptides in affective disorders is suggested by many investigators. Somatostatin-like immunoreactivity (SS-LI) and neuropeptide Y-like immunoreactivity (NPY-LI) concentrations are demonstrated to be reduced in cerebrospinal fluid from depressed patients. We have shown that long-term treatment with serotonin uptake inhibitors, clomipramine and zimelidine, reduce brain SS-LI concentrations in the rat. We have studied the effect of serotonergic agents on regional brain SS-LI and NPY-LI concentrations in rats. Long-term treatment with 5-hydroxytryptamine (5-HTP), a serotonin precursor, caused reductions in SS- and NPY-LI levels in the hypothalamus. SS- and NPY-LI concentrations in the brain were markedly elevated by treatment with p-chlorophenylalanine, a serotonin synthesis inhibitor. Intracerebroventricular administration of 5,7-dihydroxytryptamine, a serotonin neurotoxin, resulted in elevations of both peptides in the brain. These results suggest a inhibitory role for the serotonergic system in the brain in the regulation of SS and NPY.
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PMID:Effect of serotonergic agents on regional concentrations of somatostatin- and neuropeptide Y-like immunoreactivities in rat brain. 136 20

Specimens of the sigmoid colon were obtained from male and female patients (n = 11) with carcinoma of the colon or rectum and studied immunohistochemically for vasoactive intestinal polypeptide-, somatostatin-, substance P-, neuropeptide Y-, calcitonin gene-related peptide-, met- and leu-enkephalin-, 5-hydroxytryptamine-, and dopamine beta-hydroxylase-containing nerves. In the subdivisions of the submucous plexus (namely, Schabadasch's, Meissner's, and the intermediate plexuses), substance P- and vasoactive intestinal polypeptide-immunoreactive nerve fibers were the most numerous, and equal densities of these nerves were found in all three layers. In contrast, few neuropeptide Y-, met-enkephalin-, leu-enkephalin-, calcitonin gene-related peptide-, somatostatin-, 5-hydroxytryptamine-, and dopamine beta-hydroxylase-immunoreactive nerves were found in these regions. The nerve cell bodies of the submucous plexus contained vasoactive intestinal polypeptide, substance P, leu-enkephalin, somatostatin, and 5-hydroxytryptamine but not neuropeptide Y, met-enkephalin, calcitonin gene-related peptide, and dopamine beta-hydroxylase. Vasoactive intestinal polypeptide-containing nerve cell bodies were found in all three subdivisions. Substance P-, leu-enkephalin-, and somatostatin-immunoreactive nerve cell bodies were found in Schabadasch's plexus and the intermediate region of the submucous plexus, but they were absent from Meissner's plexus; 5-hydroxytryptamine-containing nerve cell bodies were only observed in Schabadasch's plexus. The possible function of the neuropeptide-, dopamine beta-hydroxylase-, and 5-hydroxytryptamine-containing neurons in the different layers of the submucous plexus is discussed.
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PMID:Peptide-containing neurons in different regions of the submucous plexus of human sigmoid colon. 848 77

The present work was undertaken to determine by immunocytochemical methods which of the putative enteric neurotransmitters are contained in axons supplying the guinea-pig taenia coli and what proportion of axons is accounted for by the presence of these substances. Numerous fibres displayed immunoreactivity for dynorphin (DYN), enkephalin (ENK), gamma-aminobutyric acid (GABA), nitric oxide synthase (NOS), substance P (SP) and vasoactive intestinal peptide (VIP), but, in contrast to other gut regions, fibres showing immunoreactivity for gastrin-releasing peptide, galanin and neuropeptide Y were rare in the taenia. Fibres reactive for calbindin, calcitonin gene-related peptide, cholecystokinin, 5-hydroxytryptamine and somatostatin were also rare. Tyrosine hydroxylase-like immunoreactivity (TH-LI) was present in numerous fibres that disappeared after extrinsic denervation, a procedure that did not detectably affect any of the other major groups of fibres. Simultaneous staining of extrinsically denervated preparations revealed that SP-LI and VIP-LI were located in separate fibres, and ultrastructural studies showed these to be 58% and 33% of intrinsic fibres supplying the muscle. Immunoreactivity for the general marker, neuron-specific enolase, was located in 95-98% of axons. ENK-LI and DYN-LI were in the same axons, and similar proportions of the fibres with either SP-LI or VIP-LI, about 85%, contained immunoreactivity for ENK and DYN. All VIP-LI fibres, but no SP-LI fibres, were reactive for NOS. The results imply that the taenia of the guinea-pig caecum is innervated by two major groups of enteric neurons: (i) excitatory neurons that contain ACh, SP, other tachykinins, and, in most cases, DYN-LI and ENK-LI; and (ii) inhibitory neurons that contain NOS-LI, VIP-LI, in most cases, the two opioids and, quite probably, ATP as a transmitter. GABA-LI is contained in a smaller population of intrinsic axons. Even though the taenia represents one of the simplest tissues for examining transmission from enteric neurons to intestinal muscle, it shares some of the complexity of other regions, in that four major axon types supply the muscle and both the enteric excitatory and enteric inhibitory neurons contain multiple transmitters.
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PMID:Light- and electron-microscopic immunochemical analysis of nerve fibre types innervating the taenia of the guinea-pig caecum. 138 81


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