Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enterochromaffin (EC) cell system is distributed throughout the entire gastrointestinal tract. Enterochromaffin cells are the major source of intestinal serotonin (5-HT), but separate subpopulations of EC cells may synthesize and store peptides as substance P (SP), motilin, and enkephalin as well. Of special interest is that 5-HT and SP, which may coexist in EC cells, have several functional similarities, i.e., inhibition of gastric acid secretion, stimulation of intestinal motility, and secretion of water and electrolytes. Carcinoid tumors are derived from the gut endocrine system. Depending on site of origin, carcinoids are divided into foregut, midgut, and hindgut derivatives with different clinical symptoms. A common biochemical feature of midgut carcinoids is the production of 5-HT and SP. Histochemically, midgut carcinoids are characterized by the argentaffin reaction--a direct reduction of silver salts owing to 5-HT. Specific antisera for the immunocytochemical demonstration of secretory products are available as well. Despite their relative infrequency, carcinoids are the most common small intestinal tumors. The common appendix tumors generally have a benign clinical course, whereas the small intestinal tumors have different growth patterns and frequently metastasize with increasing size, and may thus give rise to the carcinoid syndrome (diarrhea, facial flush, right-sided cardiac valvular disease, and asthma). Carcinoid symptoms first appear when hepatic inactivation of 5-HT is exceeded, unless the carcinoid has an extraintestinal localization, for example, ovarian lesions may elicit symptoms in the absence of hepatic disease owing to direct secretion into systemic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serotonin and carcinoid tumors. 241 66

The plasma concentrations of neuropeptides (neurotensin, substance P, motilin, somatostatin, vasoactive intestinal peptide and gastrin-releasing peptide), the urinary excretion of 5-hydroxyindoleacetic acid and serotonin, and the platelet concentration of serotonin were compared in 133 patients who could be assigned to one of four groups. These groups were as follows: carcinoid tumors present; history of carcinoid tumors; miscellaneous tumors present; and non-tumor diseases. The test with the most sensitivity (i.e., patients with carcinoid tumors labeled positive) and the test with the most specificity (i.e., patients without carcinoid tumors labeled negative) for the presence of carcinoid tumors was determined. Urinary 5-hydroxyindoleacetic acid excretion had a sensitivity of 73 percent and a specificity of 100 percent; the plasma concentration of substance P had a sensitivity of 32 percent and a specificity of 85 percent; and the plasma concentration of neurotensin had a sensitivity of 41 percent and a specificity of 60 percent. Even when basal plasma concentrations of substance P and neurotensin were elevated, there was no additional increase of these neuropeptides prior to ethanol-induced facial flushing. Although measurements of plasma neuropeptide levels may be helpful in occasional patients with carcinoid tumors, it is concluded that measurements of serotonin overproduction--such as 5-hydroxyindoleacetic acid excretion--are of more general value.
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PMID:Role of neuropeptides and serotonin in the diagnosis of carcinoid tumors. 243 80

Motilin, normally present in a specific cell type in the upper small intestine, is believed to have a physiologic role in initiating the interdigestive migrating motor complex. Motilin may play a pathophysiologic role in the diarrhea in the irritable bowel syndrome, the dumping syndrome, chronic liver disease, and chronic renal failure. Furthermore, increased frequency of bowel movements is an important symptom in patients with the carcinoid syndrome. We have studied 73 patients with metastatic carcinoid tumors with regard to stool frequency and plasma concentration of motilin and neuropeptide K (NPK) and diurnal urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA). Thirty-eight (52%) of the 73 patients had elevated (greater than 126 pmol/l) plasma concentrations of motilin, whereas 59 (81%) of the patients had diarrhea. The increased frequency of bowel motions correlated significantly (p less than 0.01) with the plasma concentrations of motilin, whereas no significant correlation with 5-HIAA and NPK was found. High-performance liquid chromatography of plasma extracts showed a single component eluting in the position of synthetic porcine motilin. However, extracts from five carcinoid tumors did not contain any significant levels of motilin. Carcinoid tumors are known to contain and secrete several biologically active substances such as serotonin, histamine, prostaglandins, and tachykinins, which are likely to cause disturbances of intestinal secretion and motility, which in turn might release motilin from the motilin-containing cells of the small intestine. The increased motilin levels might then participate in a vicious diarrhea circle together with the other agents.
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PMID:Motilin in plasma and tumor tissues from patients with the carcinoid syndrome. Possible involvement in the increased frequency of bowel movements. 244 32

Gastrointestinal hormones and regulatory peptides of the gastrointestinal tract (GIT) influence many digestive functions and therefore it is essential in diseases of the GIT to search also for changes of GIT hormones in plasma or for an altered response of the target organ to hormonal abnormalities. An unequivocal physiological function is known so far only in gastrin, cholecystokinin, secretin, gastric inhibitory polypeptide, vasoactive intestinal polypeptide, motilin, somatostatin, glucagon and pancreatic polypeptide. The authors analyzes therefore different nosological unites, or clinical syndromes associated with excessive production of gastrin, vasoactive intestinal polypeptide, glucagon and somatostatin. He discusses also the syndrome of malignant carcinoid caused by excessive formation of serotonin in the enterochromaffin cells of the GIT which by its symptoms can imitate some apudomas of the GIT.
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PMID:[Hormonal changes in diseases of the gastrointestinal tract]. 280 Mar 78

The 24 endocrine pancreatic tumors and 14 carcinoids were examined immunohistochemically for cholecystokinin, insulin, gastrin, GIP, glucagon, sercretin, VIP, motilin, neurotensin, pancreatic polypeptide (PP), somatostatin, and ACTH. In 12 tumors of the pancreas more than one peptide-containing cell type was observed. The clinical symptoms showed hypersecretion of only one of the hormones, however. The midgut carcinoids (jejunum, appendix) represented the classical view of the carcinoid as an argentaffin cell tumor secreting 5-hydroxytryptamine. Tumors originating in the foregut (bronchus, stomach, duodenum) and hindgut carcinoids (rectum) were nonargentaffine, containing and secreting various polypeptide hormones. We conclude that light microscopic immunohistochemical methods are useful in distinguishing endocrine from nonendocrine tumors and multihormonal syndromes (MEA) in the classification of predominant hormone-secreting tumors.
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PMID:[Endocrine tumors of the gastrointestinal and pancreatic systems. Multiple endocrine adenoma from another viewpoint]. 610 39

A well-differentiated colonic adenocarcinoma containing large numbers of gastrointestinal neuroendocrine cells is presented. The presence of neurosecretory granules was confirmed by electron microscopy. Immunocytochemistry showed large numbers of serotonin-containing tumor cells and lesser numbers of somatostatin, gastrin, motilin, secretin and neurotensin-containing cells. Some of these hormones are not normally present in the colon in significant numbers of cells. The presence of several cell types within a single tumor supports the concept that the normal epithelial cells of the gastrointestinal mucosa are derived from a common endodermal stem cell. There exists a spectrum of tumors ranging from the classical adenocarcinoma to the classical carcinoid, and this report identifies the position of this case within that spectrum.
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PMID:A colonic adenocarcinoma with argentaffin cells. An immunoperoxidase study demonstrating the presence of numerous neuroendocrine products. 613 Aug 35

A total of 87 surgical cases of gastric carcinoma including 3 carcinoid tumors were investigated with the methods of silver reaction and immunoperoxidase stain for 8 different brain-gut hormones. Argyrophil (AP) cells were demonstrated in 38 cases (44%), argentaffin (AF) cells in 18 (21%) and endocrine cells in 13 (14%). The occurrence of endocrine cells had no relation with histological types. Glicentin cells were demonstrated in 10 cases, somatostatin in 7, motilin in 3, beta-endorphin in 2 and gastrin in one. Endocrine cells appeared generally in small numbers except one carcinoid tumor which had numerous somatostatin cells. No single cell positive for more than two kinds of hormones could be demonstrated. Two undifferentiated carcinomas looking like carcinoid tumors had argyrophil cells and endocrine cells of either somatostatin or beta-endorphin. These results suggest that carcinoid-like carcinoma or endocrine cell carcinoma may lie on the intermediate state between carcinoma and carcinoid tumor.
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PMID:Immunohistochemical localization of brain-gut hormones in gastric carcinoma with relation to argyrophil cells. 614 33

An argentaffin carcinoid tumour of the caecum which contained serotonin (167 micrograms/g) and consisted predominantly of EC1-cells, was analysed for the presence of peptides using immunohistochemical, biochemical and pharmacological methods. A very high content of 3.9 micrograms/g of immunoreactive substance P was found. The distribution of cells staining positively for substance P matched that of cells containing serotonin. While some immunoreactive somatostatin (3.2 ng/g) was present in the tumour, neurotensin, glucagon, gastrin, and motilin were not found. Part of the substance P immunoreactivity measured most likely represents authentic substance P: it behaved like substance P in two chromatographic systems and in two bioassays, and its activity on the guinea pig ileum was abolished by specific tachyphylaxis towards substance P.
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PMID:Substance P in the argentaffin carcinoid of the caecum: biochemical and biological characterization. 616 90

The intestinal carcinoid tumors of 26 patients were stained for the presence of serotonin, gastrin, somatostatin, motilin, secretin, glucagon, pancreatic polypeptide, ACTH, and neurotensin. Argentaffin and argyrophil stains were also performed in all cases. Thirty-five separate tumors (counting metastases and multiple primaries) from the 26 patients were studied. Serotonin was present in 30 of the 35 tumors. Nineteen tumors contained serotonin only. Fourteen tumors contained multiple neuroendocrine products. One tumor contained gastrin only. One tumor did not stain immunohistochemically, but was argyrophilic. Metastatic deposits were studied in nine patients. Some metastases produced the identical neuroendocrine products as the primary tumor, whereas others produced either additional or fewer hormones than the primary tumor. Moreover, different metastases from the same primary tumor were observed to produce different hormones. Argyrophilic cells were present in all cases and were much more numerous than cells staining by immunohistochemistry. Argyrophilic cells probably contain monoamines and polypeptide hormones in addition to those studied in this series. The argyrophil stain was the best general stain in this study for the demonstration of neuroendocrine cells. Argentaffin staining was negative in ten cases that were serotonin positive and two argentaffin positive cases were serotonin negative. The carcinoid syndrome, as clinically defined by the presence of flushing and diarrhea, was noted in five patients, all of whom had serotonin-containing small bowel carcinoids. Endocrine-related symptoms were not clinically appreciated in the remaining patients.
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PMID:The neuroendocrine products of intestinal carcinoids. An immunoperoxidase study of 35 carcinoid tumors stained for serotonin and eight polypeptide hormones. 618 28

Whereas serotonin and substance P stimulate in-vivo and in-vitro myoelectric activity in the small intestine, their effects on transit are unclear. We used a validated in-vivo transit model in the chloral hydrate-anaesthetized rat to study the effects of serotonin, substance P and motilin, three putative mediators of carcinoid diarrhoea, on transit through the upper digestive tract. Intra-arterial serotonin accelerated gastric emptying of a radiolabelled liquid, while motilin accelerated overall upper gastrointestinal transit. Substance P slowed overall upper gastrointestinal transit without altering gastric emptying. The antagonists to serotonin receptor subtypes, R-zacopride (5-HT3) and ketanserin (5-HT2), also accelerated rat gastric emptying of liquids; in contrast, a 5-HT4 agonist, SC53116, resulted in a less pronounced effect on gastric emptying at the dose tested. We conclude that circulating substance P is unlikely to be an important accelerator of transit through the upper digestive tract; in contrast, hyperserotoninaemia significantly accelerates transit through the stomach, and 5-HT2 and 5-HT3 receptor subtypes may play a role in the motor effects of serotonin in the stomach.
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PMID:Effect of putative carcinoid mediators on gastric and small bowel transit in rats and the role of 5-HT receptors. 767 34


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