Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to understand better the neuronal circuitry involved in the regulation of gut functions, we have studied the distribution and projections of those enteric neurons in the rat intestines that contain vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), galanin, substance P (SP), calcitonin gene-related peptide (CGRP), gastrin releasing peptide (GRP), somatostatin and enkephalin. The origin of the peptide-containing nerve fibers was examined by immunocytochemistry after extrinsic denervation. Most of them were found to be intramural in origin, each population displaying its own characteristic topographic distribution. The projections of each neuronal population were studied immunocytochemically by examining the subsequent axonal degeneration after local severing of nervous pathways. This study revealed that myenteric neurons issue predominantly descending projections to other myenteric ganglia and to the muscle layers. Submucous neurons project to other submucous ganglia and to the mucosa and submucosa. Most of these neurons issue both ascending and descending projections. The projection distances varied considerably between the different neuronal populations, the majority being in the range of 4-10 mm. Myenteric GRP and galanin neurons in the small intestine issued the longest projections, 20 and 15 mm, respectively. The shortest projections were those issued from myenteric VIP/NPY neurons and submucosal galanin and GRP neurons in the small intestine and from submucosal VIP neurons in the large intestine (2 mm in length). On the whole our results on the projections of enteric neurons in the rat agree with observations in the guinea pig and dog. However, there are species differences that remain to be explained.
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PMID:Projections of enteric peptide-containing neurons in the rat. 247 1

The regulation by gastrointestinal polypeptide hormones of contraction and relaxation of functionally isolated smooth muscle cells from gastric antrum of the rabbit has been investigated. Gastrin, cholecystokinin (CCK-8) and motilin induced a rapid contraction of isolated cells: significant response occurred within a 5-sec incubation with these peptides and maximal response (40% decrease in cell length) after 30 sec. A higher sensitivity of smooth muscle cells to gastrin and CCK-8 than to motilin stimulations was demonstrated (EC50 = 10 pM for both gastrin and CCK-8 and EC50 = 1 nM for motilin). The minimal gastrin fragment required to get full contraction was the C-terminal pentapeptide amide common to gastrin and CCK. Proglumide inhibited gastrin- or CCK-8- but not motilin-induced contractions with an IC50 of 50 microM. contraction induced by gastrin and motilin required normal levels of extracellular calcium, whereas that due to CCK-8 seemed to be independent of extracellular calcium. Vasoactive intestinal polypeptide (VIP) caused a relaxation of smooth muscle cells maximally contracted by carbachol or CCK-8 or gastrin (EC50 = 2.2 nM) with a parallel increase in intracellular cAMP content.
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PMID:Gastrointestinal hormone receptors on isolated smooth muscle cells from gastric antrum of the rabbit. 255 13

Octreotide is a long-acting cyclic octapeptide with pharmacologic actions mimicking those of the natural hormone somatostatin. It can suppress the secretion of serotonin, as well as the gastroenteropancreatic peptides gastrin, vasoactive intestinal peptide (VIP), insulin, glucagon, secretin, motilin, and pancreatic polypeptide. It also suppresses growth hormone and decreases splanchnic blood flow. Octreotide is completely and rapidly absorbed following subcutaneous injection and has an elimination half-life of 1.5 hours. Clinical trials reviewed here show octreotide useful in the treatment of diarrhea associated with VIP secreting tumors, as well as diarrhea and flushing associated with carcinoid syndrome, both conditions for which the drug is approved. Clinical trials involving the use of octreotide in the treatment of acromegaly are also reviewed. Adverse reactions to octreotide are mild to moderate and most commonly involve injection site pain and diarrhea. Drug interactions are apparently related to the drug's pharmacologic effects. Octreotide is given subcutaneously two to three times daily, with daily doses ranging from 50mcg to 1,500mcg per day. Further research appears necessary to clarify dosing issues.
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PMID:Debut of a somatostatin analog: octreotide in review. 255 39

The autonomic nervous system includes, side by side with the sympathetic and parasymathetic systems, a third, non-adrenergic and non-cholinergic system called NANC. The mediators in this system are peptides acting as neurotransmitters, i.e. neuropeptides. The NANC system has two components: bronchodilator and bronchoconstrictor. The bronchial relaxant system, called non-adrenergic inhibitory system, has several neurotransmitters, viz.: vasoactive intestinal peptide (VIP), isoleucine histidine peptide (IHP) and methionine histidine peptide (MPH), all derived from a common precursor: pre-pro VIP. MHP has been described in man and IHP in some animal species. VIP relaxes the bronchial smooth muscle, is vasodilator and exerts cellular effects in phagocytes, lymphocytes and mast cells. VIP receptors are present on cells. The other component, called non-cholinergic excitatory system, has tachykinins as neuromediators, including substance P, neurokinins A and B, neuropeptide K and calcitonin gene related peptide (CGRP). Substance P contracts the bronchi, increases mucus secretion, dilates vessels and also exerts cellular effects in lymphocytes and phagocytes. Tachykinins act through receptors 3 types of which are now known: NK 1, NK 2 and NK 3. Other neuropeptides have been isolated, including galanin, neuropeptide Y, bombesin, gastrin releasing peptide, enkephalins and katacalcin. The coexistence, in pre- and post-synaptic positions, of the conventional mediators (noradrenaline, acetylcholine) and neuropeptides leads to the concept of co-transmission and makes the notion of nerve impulse transmission more complex. The development of neuropeptide agonists and antagonists opens new therapeutic prospects in the management of asthma.
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PMID:[Neuropeptides and respiratory diseases: prospects in the treatment of asthma]. 257 26

The occurrence and distribution of peptide-containing nerve fibers to the cerebral circulation are described. Immunocytochemical studies have revealed that cerebral blood vessels are invested with nerve fibers containing neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), peptide histidine isoleucine (PHI), substance P (SP), neurokinin A (NKA), and calcitonin gene-related peptide (CGRP). In addition, there are studies reporting the occurrence of putative neurotransmitters such as cholecystokinin, dynorphin B, galanin, gastrin releasing peptide, vasopressin, neurotensin, and somatostatin. The nerves occur as a longitudinally oriented network around large cerebral arteries. There is often a richer supply of nerve fibers around arteries than veins. The origin of these nerve fibers has been studied by retrograde tracing and denervation experiments. These techniques, in combination with immunocytochemistry, have revealed a rather extensive innervation pattern. Several ganglia, such as the superior cervical ganglion, the sphenopalatine ganglion, the otic ganglion, and small local ganglia at the base of the skull, contribute to the innervation. Sensory fibers seem to derive from the trigeminal ganglion, the jugular-nodose ganglionic complex, and from dorsal root ganglia at level C2. The noradrenergic and most of the NPY fibers derive from the superior cervical ganglion. A minor population of the NPY-containing fibers contains VIP instead of NA and emanates from the sphenopalatine ganglion. The cholinergic and the VIP-containing fibers derive from the sphenopalatine ganglion, the otic ganglion, and from small local ganglia at the base of the skull. Most of the SP-, NKA-, and CGRP-containing fibers derive from the trigeminal ganglion. Minor contributions may emanate from the jugular-nodose ganglionic complex and from the spinal dorsal root ganglia. NPY is a potent vasoconstrictor in vitro and in situ. VIP, PHI, SP, NKA, and CGRP act via different mechanisms to induce cerebrovascular dilatation. The sympathetic, the parasympathetic, and the sensory systems appear to be involved in modulating cerebrovascular tone in hypertension and in conditions of threatening vasoconstriction, e.g., subarachnoid hemorrhage and migraine.
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PMID:Neuropeptides in the cerebral circulation. 270 77

The central nervous system effects of neuropeptides on gastric acid and duodenal bicarbonate secretions were examined. In freely moving rats, i.c.v. administration of thyrotropin-releasing hormone (TRH), human gastrin-17 (hG-17) and the somatostatin analogue, desAA 1,2,4,5,12,13 [D-Trp8]somatostatin (ODT8-SS), significantly increased gastric acid secretion, while vasoactive intestinal peptide (VIP) had no effect. In the order of potency and efficacy, the following peptides decreased acid secretion: bombesin (BOM) greater than calcitonin gene-related peptide (CGRP) greater than calcitonin (CT) greater than corticotropin-releasing factor (CRF) greater than beta-endorphin (beta-END) greater than neurotensin (NT). In anesthetized rats, none of these peptides significantly altered proximal duodenal bicarbonate secretion. In awake, freely moving rats, cerebroventricular administration of CGRP significantly decreased while ODT8-SS, TRH and CRF significantly increased duodenal bicarbonate secretion. beta-Endorphin, VIP, CT, BOM, NT and hG-17 given i.c.v. did not significantly alter the bicarbonate response. These results indicate that neuropeptides administered into the central nervous system modulate gastric acid as well as duodenal bicarbonate secretions in awake, freely moving rats in a differentiated fashion. CGRP inhibits both acid and bicarbonate secretions, a somatostatin analogue and TRH both stimulate acid and bicarbonate secretions and CRF inhibits gastric acid but stimulates duodenal bicarbonate secretions.
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PMID:Effects of neuropeptides on gastric acid and duodenal bicarbonate secretions in freely moving rats. 271 Sep 63

A patient presenting clinically with the glucagonoma syndrome had high plasma glucagon levels (1920 ng/l) and at laparotomy, a pancreatic islet cell tumour was removed. The tumour was dispersed and placed in culture where it remained viable for 63 days. The tumour cells secreted immunoreactive (IR) glucagon at levels up to 2400 ng/l as detected by a C-terminal glucagon specific antibody and 85 400 ngequiv./l as measured by an N-terminal glucagon specific antibody. The difference between these two levels was attributed to the presence of different molecular forms of glucagon measured with the N-terminal specific antibody. IR insulin (up to 302 mU/l) and IR somatostatin (up to 2500 ng/l) were also detected. There was no direct or inverse correlation between different hormone levels. Small but significant levels of N-terminal and C-terminal vasoactive intestinal peptide (VIP) were detected in some cultures but there was no evidence of gastrin or ACTH. Glucagon and somatostatin secretion persisted for the duration of the culture (63 days) but insulin concentrations declined. Incubation of cultures with somatostatin (1 ng/ml) caused a 75% decrease in glucagon levels, while insulin (1000 mU/l) produced a 70% inhibition of somatostatin.
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PMID:Multiple hormone secretion by a human pancreatic glucagonoma in culture. 286 20

Cells with argyrophil granules were searched for in 131 consecutive specimens obtained from endometrial curettage. Particular care was taken with the fixation methods to avoid a false positivity to the silver impregnation according to Grimelius. We did not consider the grossly argyrophilic positivity on the cellular apex or of the whole cytoplasm, which was partially reduced by diastase digestion and probably due to the presence of glycogen and secretory mucoproteins. Cells with thin argyrophilic granules similar to those observed in endocrine APUD cells were present among glandular cells and/or among stromal cells in 15 of 131 examined specimens. They concerned 5 cases of proliferative endometrium, 3 of secretive endometrium, 5 of hyperplasia, and 2 of carcinoma. In 8 of the 15 cases with argyrophilic cells, immunohistochemical studies with the PAP method showed cells with the presence of FSH, S-100 protein, somatostatin, vasoactive intestinal peptide (VIP), gastrin, and neuron-specific enolase (NSE). The significance and origin of these cells in normal and neoplastic endometrium are discussed.
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PMID:Presence of cells with argyrophil granules in normal, hyperplastic, and neoplastic endometrium. 288 Apr 17

The oesophageal pH was recorded for 3 h after a test-meal in 27 healthy control subjects (group I), 40 patients with alcoholic cirrhosis (group II), and 22 patients with a normal liver and symptoms of gastro-oesophageal reflux (control refluxers). Gastro-oesophageal reflux was observed in 10 of the cirrhotic patients. Marked reflux episodes lasted longer in cirrhotic refluxers than in control refluxers (P less than 0.05). The frequency of ascites, bleeding from ruptured oesophageal varices, peripheral neuropathy and hepatic encephalopathy were not significantly different according to presence or absence of reflux. Plasma concentrations of gastrin, somatostatin, motilin and vasoactive intestinal peptide (VIP) were measured in groups I and II. Fasting plasma motilin levels, and the release of motilin and of VIP after the meal were higher in group II than in group I. Basal levels and post-prandial profiles of the four peptides tested did not differ between cirrhotics with or without gastro-oesophageal reflux. We conclude that in patients with alcoholic cirrhosis: gastro-oesophageal reflux is frequent (25%) and characterized by prolonged reflux episodes; reflux is not correlated with the degree of liver failure and plays no significant role in the rupture of oesophageal varices; and raised plasma motilin and VIP levels cannot account for the high incidence of reflux in cirrhotics.
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PMID:Gastro-oesophageal reflux and alcoholic cirrhosis. A reappraisal. 288 50

A total of ten 6-month-old male rhesus monkey (Macaca mulatta) infants, born full-term, were positive-pressure ventilated with greater than 95% oxygen or room air (controls). A protocol was used which closely simulated pediatric intensive care. To test if regulatory peptides were affected by the oxygen treatment, and to search for an early marker of oxygen toxicity, lung tissue samples and systemic mixed venous blood were collected at 6, 12 and 24 hours after onset of treatment. The peptides, gastrin releasing peptide (GRP), calcitonin gene-related peptide (CGRP), peptide YY (PYY), vasoactive intestinal peptide (VIP) and somatostatin (SOM), were quantitated in lung tissue extracts and plasma using radioimmunoassay. Lung tissue GRP, CGRP, and PYY levels appeared to decrease gradually with time, perhaps as a result of the positive pressure ventilation procedure. GRP and CGRP levels decreased less among monkey infants ventilated with oxygen, thus they were significantly higher at 24 hours than in air ventilated controls. VIP levels were significantly lower among tests compared to controls at that time. Blood peptide levels did not change with oxygen treatment. These results suggest that tissue concentrations of certain pulmonary regulatory peptides can become altered by ventilation with greater than 95% oxygen. A blood borne peptide marker was not identified.
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PMID:Oxygen toxicity in the infant rhesus monkey: effects on regulatory peptides in lung and blood. 290 54


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