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)

Eighteen endocrine pancreatic tumors were examined for the occurrence of cells producing insulin, glucagon, gastrin, human pancreatic polypeptide (HPP), and vasoactive intestinal polypeptide (VIP) and for A1 cells. More than half of the tumors were mixed, i.e., they contained more than one type of hormone-producing cell. The clinical symptoms were attributable only to one of the hormones produced by the mixed tumors. Three of four tumors causing the watery diarrhea syndrome contained both VIP and HPP cells. In one such tumor there was a strong predominance of HPP cells; the serum HPP levels of this patient were a thousandfold elevated, whereas her VIP levels were within the normal range. Several lines of evidence point to HPP as a possible agent causing the watery diarrhea syndrome. In many of our patients, HPP cells hyperplasia was present in the extratumoral pancreas. Such hyperplasia may give rise to the raised serum HPP levels seen in many patients having endocrine pancreatic tumors.
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PMID:Occurrence of human pancreatic polypeptide in pancreatic endocrine tumors. Possible implication in the watery diarrhea syndrome. 99 36

The present experiments have been carried out in order to establish whether the stimulatory effect of bombesin on the chicken gastric acid secretion is a direct effect or is mediated by the release of hormones, such as the Avian Pancreatic Petide and/or Gastrin. removal of the pancreas, which is known to be the site of starage of the Avian Pancreatic Polypeptide, does not produce any decrease of the stimulant effect of bombesin on gastric secretion. Removal of the zone between the gizzard and duodenum, which shows histological features similar to those of the mammalian antrum and in which gastrin cells have been described, sharply decreases the basal values of gastric secretion as well as the stimulant effect of bombesin, while the effectiveness of caerulein, a gastrin-like peptide directly acting on oxintopeptic cells, is maintained. In chickens deprived of the duodenum-gizzard zone, bombesin shows a stimulant effect on pancreatic secretion indistinguishable from that observed in intact animals. It is concluded that the gastric but not pancreatic, action of bomtesin is mediated through the release of a factor(gastrin) from the gizzard-duodenum junction. Release of Avian Pancreatic Polypeptide from the pancreas is not involved in the mechanism of the action of bombesin on gastric secretion of the chicken.
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PMID:On the mechanism of action of bombesin on gastric and pancreatic secretion of the chicken. 101 25

Based on morphological and histochemical data, the Authors describe the distribution of "EC" (5-HT-producing) and of the other endocrine cells of the "APUD" series (polypeptide hormone-producing) in the gastro intestinal tract of weaned and unweaned 3-4 month old calves. The results demonstrate that: -- no difference concerning the different diet can be correlated; -- no endocrine cell is present in the vorestomachs; -- the "EC" cells in the abomasum prevail in the fundus glands; they are demonstrable also in every tract of the intestine and are more numerous in the duodenum and in the rectum; -- within the "APUD" series four cellular types are demonstrable in the abomasum; two are in the cardias, one in the fundus and one in the pylorus glands; the last one probably corresponds to the gastrin-producing "G" cells. -- In the small intestine, particularly numerous in the duodenum, a probably heterogeneous family of endocrine cells is present, while in the coecum, in the colon and, above all, in the rectum, cells probably corresponding to "EG" cells are identifiable. These results are compared to those previously obtained in the adult Cattle: remarkable differences are demonstrable only within "APUD" cells of abomasum.
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PMID:[Distribution of the enterochromaffin ("EC") cells and those of the "APUD" series in the gastrointestinal tract of the calf]. 102 38

Hypocalcemia following gastrin administration occurs in thyroparathyroidectomized (TPTX) as well as thyroid intact rats. Hypophosphatemia does not accompany the hypocalcemia induced by gastrin. These data suggest that a mechanism other than release of calcitonin from the thyroid gland may be involved in this response in the rat. Neither adrenalectomy, nephrectomy, nor excision of the pancreas and small and large intestine altered the hypocalcemic response to gastrin. Gastrectomy, however, eliminated all hypocalcemia following administration of this polypeptide in both thyroid intact and TPTX rats. Removal of the antrum of the stomach did not influence the hypocalcemic response to gastrin. Resection of the proximal 75% of the stomach, however, inhibited the hypocalcemic response to gastrin as did total gastrectomy. Thus, in the rat, the proximal stomach appears to play an important role in mediating this response.
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PMID:The importance of the stomach in gastrin-induced hypocalcemia in the rat. 112 84

Vagally denervated (Heidenhain) pouch acid outputs and serum gastrin concentrations, basal and in response to feeding, were measured in dogs before and after massive intestinal resection. Both 24-hr and postprandial Heidenhain pouch acid outputs increased (P less than 0.01) after intestinal resection. Increases in serum gastrin concentrations following feeding were greater after massive resection of the small intestine. There was an excellent correlation (r= 0.967; P less than 0.005) between increases in serum gastrin concentrations and Heidenhain pouch acid outputs after intestinal resection. These studies support and are consistent with the hypothesis that the polypeptide hormone gastrin plays a role in the production of the gastric acid hypersecretion which, in both dogs and man, frequently results from massive resection of the small intestine.
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PMID:Changes in canine gastric acid output and serum gastrin levels following massive small intestinal resection. 115 49

A peptide which stimulates gastric acid secretion in the rat has been isolated from the normal porcine pancreas. It consists of 13 amino acids and has a molecular weight of 1286. It has been named GSP (gastrosecretagogue pancreatic peptide) on account of its main biological activity. Although its influence on gastric acid secretion is gastrin-like, there are marked biochemical and immunological differences between gastrin and GSP. The two substances are separable from each other by Sephadex gel filtration, by ion-exchange chromatography, and by disc electrophoresis. Furthermore, there are differences in the UV-absorption spectrum and in the amino acid composition. GSP does not react with gastrin antibodies in a radioimmunological system. GSP is considered to be a new polypeptide hormone by means of which the pancreas plays a role in the regulation of gastric acid secretion.
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PMID:[Extraction and characterization of a gastrosecretagogue peptide from the pancreas (author's transl)]. 122 17

We have studied the effects of several porcine enteric polypeptide hormones on trout calcitonin (tCT) secretion in long-lived monolayer cultures of calcitonin-secreting (C-) cells derived from trout ultimobranchial glands. Gastrin, pancreozymin (CCK-PZ), glucagon, and secretin have dose-related stimulatory effects on tCT secretion; the distinct effects of secretin on tCT secretion are in contrast to its lack of CT secretagogue activity in some mammals. Synthetic peptide hormones and/or their structural analogs have variable secretory effects which correspond in general to the potency of the analogs for the well-recognized biological actions of these various peptide hormones in mammals. Although enteric peptide hormones are present in fish, their physiological role in the regulation of CT secretion has not been studied. These in vitro studies indicate a possible role for these hormones in the control of tCT secretion and support the concept that there are differences in the regulators of C-cell function in higher and lower vertebrates. In vitro studies of fish CT secretion are needed to establish the physiological significance of these in vitro studies of fish C-cell function.
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PMID:Calcitonin secretion in vitro. II. Regulatory effects of enteric mammalian polypeptide hormones on trout C-cell cultures. 126 21

1. 125I-labelled secretin bound rapidly and specifically to membranes from cat pancreas. Binding of labelled hormone was competitively inhibited by unlabelled secretin in the same range of concentrations that stimulated pancreatic adenylate cyclase in these membranes. The dissociation constant of the membrane binding sites for unlabelled secretin as evaluated by these displacement experiments was 4.1-10(-9) M and the number of binding sites 1.0 pmol per mg of membrane protein. 2. Studies using different concentrations of [125I]secretin (at a constant ratio of labelled to unlabelled hormone) revealed a similar value of 4-4-10(-9) M for the dissociation constant. 3. Both the association and dissociation rate constants of [125I]secretin binding were temperature sensitive; the dissociation rate constant increased more rapidly with increase in temperature. The ratio k-1/k+1 (at 22 degrees C) gave a dissociation constant of 3.7-10(-9)M which agrees closely with the figure obtained from equilibrium data. These data indicate that 125I-labelled secretin and unlabelled secretin bind to the same binding site on pancreatic membranes, with high affinity. 4. Unlabelled secretin stimulated pancreatic adenylate cyclase with an apparent Km of 8.4-10(-9) M, while [125I]secretin apparently did not stimulate the adenylate cyclase. Together with the binding data this might suggest that different portions of the secretin molecule are responsible for binding and adenylate cyclase activation. 5. Studies on the specificity of [125I]secretin binding carried out with various peptide hormones (glucagon, human gastrin, pancreozymin and caerulein) which are all inefficient in stimulating pancreatic fluid secretin, showed that these hormones have no influence on the binding of [125I]secretin. In contrast, vasoactive intestinal polypeptide, which stimulates pancreatic fluid and bicarbonate secretion, showed a competitive inhibition of secretin binding to the plasma membrane preparation.
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PMID:The interaction of secretin with pancreatic membranes. 127 8

The morphology and distribution of secretin (S) cells were investigated in the human and the dog. S cells were well-visualized by the indired immunofluorescence antibody technique, using a highly specific rabbit anti-secretin sera. The fluorescence reaction was not blocked by an excess amount of gastrin, cholecystokinin, glucagon, vasoactive intestinal polypeptide, or motilin, whereas secretin blocked the reaction. S cells were seen in the mucosa of the antrum and duodenum in both humans and dogs, and throughout the entire length of the canine small intestine. They were not found in the mucosa of the esophagus, fundus of the stomach, or rectum. These cells were either pyramidal in shape or pearshaped and were one-third of the size of gastrin cells. The possible significance of S-cell distribution in the antrum and small intestine is discussed.
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PMID:Secretion cells in the gastrointestinal tract. 127 7

Elucidation of receptors and mediators regulating gastric pepsinogen secretion has lagged behind understanding of the factors that control acid secretion. During the past decade, as a consequence of the development of in vitro models for studying the control of pepsinogen secretion at the cellular level, much information about chief cell receptors and signal-transduction mechanisms has been obtained, including the identification and characterization of receptors for secretin, vasoactive intestinal polypeptide, cholinergic agonists, gastrin, cholecystokinin, peptide YY, and cholera toxin. Moreover, these cell preparations have permitted secretagogue-induced changes in chief-cell calcium concentration, protein kinase C distribution, and phosphoinositide and cyclic nucleotide content to be measured and related to changes in pepsinogen secretion. This article reviews these advances, discusses areas of uncertainty and controversy, and indicates areas for future investigation.
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PMID:Gastric chief cells: receptors and signal-transduction mechanisms. 131 85


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