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)

Acid extracts of rat gut and brain contain substances that cross-react in a radioimmunoassay for the amphibian skin tetradecapeptide bombesin. Highest concentrations are present in the fundic part of the stomach, but there are significant amounts throughout the small and large intestine. Concentrations in the brain are highest in the hypothalamus. On gel filtration the rat bombesin-like immunoreactivity eluted as two major peaks. Fractionation of the second peak on cation exchange chromatography resolves this material into two further components. Intravenous infusions of partially purified preparations of the two components separated on gel filtration cause increases in serum gastrin in rats that are similar to those produced by immunochemically comparable amounts of synthetic bombesin.
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PMID:Bombesin-like peptides in mammals. 45 18

Responses of serum gastrin and gastric acid output levels were studied in four dogs before and after a bilioenteric by-pass. Serum gastrin levels during bombesin infusion were measured in eight patients submitted to Roux-en-Y hepatocholangiojejunostomy. No change was observed in acid secretion from the main stomach or from the Heidenhain pouch in dogs following biliojejunostomy. The peak acid output, however, occurred significantly earlier after diversion of bile from the duodenum. Serum gastrin levels decreased significantly in dogs after bilioenteric by-pass and in the operated patients compared with normal subjects. The possible role played by bile in the release of duodenal gastrin is hypothesized.
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PMID:Responses of serum gastrin and gastric acid output before and after bilioenteric by-pass in the dog and man. 46 45

The inhibitory effects of intravenous infusions of secretin, glucagon and caerulein on the gastric acid response to bombesin were studied in 8 duodenal ulcer patients. Bombesin was found to be a very potent stimulator of gastric acid secretion in patients with duodenal ulcer. There were no significant differences in acid outputs per 15-min period between bombesin infused in a dose of 0.9 microgram/kg/h and pentagastrin infusion administered in a maximal dose, at a rate of 6.0 microgram/kg/h. Secretin (1 U/kg/h), glucagon (30 microgram/kg/h) and caerulein (0.1 microgram/kg/h) produced significant decreases in gastric acid secretion evoked by bombesin given in a dose of 0.9 microgram/kg/h. Percentages of inhibition were 48.6, 45.2 and 35.5, respectively. It is supposed that secretin and glucagon given in pharmacological doses are capable of interfering with the action of gastrin released from antrum by means of bombesin on the parietal cell by noncompetitive kinetics. Caerulein administered in a pharmacological dosis, however, can inhibit the effect of gastrin released by bombesin on the parietal cells by a competitive kinetic.
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PMID:Inhibition of bombesin-stimulated gastric acid secretion by secretin, glucagon and caerulein in patients with duodenal ulcer. 48 52

Bombesin caused depolarization of rat or mouse pancreatic acinar cell membrane, reduction of membrane resistance, and a steep rise in amylase output from superfused pancreatic fragments. These effects were similar to those previously described for acetylcholine, cholecystokinin, and gastrin. The dose-response curves for these three effects of bombesin were very similar, with effects being detectable at concentrations of about 30 pM and maximal effects at about 10 nM. The equilibrium potential for the membrane action of bombesin, i.e., the membrane potential at which bombesin did not cause any change in membrane potential, was -16 mV. Similar values for equilibrium potential were obtained with acetylcholine, caerulein and pentagastrin. Bombesin in the higher dose range (10 nM) caused electrical uncoupling of acinar cells within an acinus, i.e., a marked increase in junctional membrane resistance. Similar uncoupling effects were observed after acetylcholine, caerulein, and pentagastrin stimulation. In conclusion, bombesin acts on the pancreatic acinar plasma membrane in exactly the same way as acetylcholine and cholecystokinin-pancreozymin. The electrical uncoupling caused by stimulation is evidence for an increase in cytosol free calcium ion concentration.
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PMID:In vitro action of bombesin on amylase secretion, membrane potential, and membrane resistance in rat and mouse pancreatic acinar cells. A comparison with other secretagogues. 61 13

In studies in dogs the gastrin response to food, to bombesin (1 micrgoram/kg-hr), and to somatostatin (2.5 and 5.0 microgram/kh-hr) plus food before and after truncal vagotomy was determined. Vagotomy caused an increase in basal levels of gastrin and in the release of gastrin after bombesin and food. Vagotomy augmented somatostatin suppression of food-stimulated gastrin release in a dose-dependent manner. We suggest that vagotomy causes a loss of both stimulatory and inhibitory vagal effects on gastrin release. Loss of vagal inhibition results in increased gastrin release to bombesin and food. Loss of vagal stimulation results in intensification of somatostatin-induced inhibition of postprandial gastrin release.
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PMID:Influence of vagus on mechanisms for stimulation and inhibition of gastrin release. 64 65

In 17 patients with postoperative recurrent peptic ulcer, incomplete antrectomy (I.A.) was found by endoscopic biopsies in 5. No evidcence of I.A. was found in the remaining 12 patients. Gastric acid output and gastrin levels were measured in basal conditions and following a calcium I.V. infusion (4 mg/kg hr of Ca++ over 4 hr) and a bombesin (BBS) I.V. infusion (15 ng/kg min over 90 min). Basal gastrin levels were significantly differnt in the two groups of patients: BBS infusion augmented significantly serum gastrin levels in all patients with I.S., while BBS infusion had no significant effect on serum gastrin levels in the group of patients without I.A. Acid output following BBS infusion showed a pattern similar to the pattern seen for gastrin. Calcium infusion augmented gastric acid secretion and gastrin levels in the patients with I.A.; however, the response to calcium could not clearly separate in all instances patients with I.A. from patients without I.A. It is concluded that the "BBS infusion test" may be heplful in the diagnosis of I.A. in patients with postoperative peptic ulcer.
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PMID:Acid and gastrin levels after bombesin and calcium infusion in patients with incomplete antrectomy. 83 53

1. Pancreatic volume flow as well as bicarbonate and protein secretion from pancreatic fistulas have been measured in response to i.v. infusion of graded doses of bombesin and related peptides containing the COOH-terminal fragment of the bombesin molecule in conscious dogs with intact antrum and in anaesthetized animals with antrectomy, or antrectomy and enterectomy. 2. Bombesin and related peptides given to conscious dogs produced a potent and dose-dependent increase in pancreatic protein output reaching a maximum equal to that induced by the octapeptide of cholecystokinin (OP-CCK) as well as a small rise in bicarbonate output attaining a peak amounting to about 10% of that evoked by secretin. The serum gastrin level rose progressively during the infusion of bombesin to reach a peak with the highest dose of peptide. 3. Bombesin infused i.v. in anaesthetized animals with resected antrum also evoked a marked increase in pancreatic protein secretion without significant changes in the serum gastrin level. Following the removal of the antrum and small intestine, bombesin failed to show any stimulation of the pancreatic secretion or any change in the serum gastrin level. It is concluded that the strong stimulatory action of bombesin and related peptides on pancreatic secretion cannot be entirely ascribed to the release of gastrin but might be attributed at least in part to the release of intestinal hormones, particularly CCK. 4. Atropine and the growth hormone-release inhibiting hormone (GH-RIH), which were shown to inhibit the release of CCK induced by duodenal perfusion of an amino acid mixture, also caused the inhibition of pancreatic protein secretion by bombesin but failed to affect the pancreatic response to OP-CCK. The results indicate that bombesin releases, in addition to gastrin, CCK from the gut by a mechanism largely dependent upon cholingeric innervation.
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PMID:Effect of bombesin and related peptides on the release and action of intestinal hormones on pancreatic secretion. 95 Jun 8

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

The effect of a protein test meal and a bombesin infusion on extragastric gastrin levels was studied in patients with truncal vagotomy, antrectomy, and gastroduodenostomy or gastrojejunostomy and in patients with total gastrectomy. In patients with vagotomy, antrectomy, and gastroduodenostomy and in patients with total gastrectomy the gastrin levels were raised by 33% and 35%, respectively, from basal after test meal, while during BBS infusion gastrin values decreased by 25% and 30%, respectively, from basal. In patients with vagotomy, antrectomy, and gastrojejunostomy, test meal and BBS infusion did not significantly alter basal gastrin values. It is concluded that BBS does not stimulate extragastric gastrin.
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PMID:Effect of bombesin on extragastric gastrin in man. 119 Feb

The spectrum of biological activity exhibited by litorin, a bombesin-like nonapeptide found in extracts of the skin of the Australian leptodactylid frog Litoria aurea was compared with that exhibited by the tetradecapeptide bombesin. 2 Litorin proved to be more potent than bombesin on isolated smooth muscle preparations and on the urinary bladder in situ. However, it was less potent on dog systemic blood pressure and kidney vasculature activation of the renen-angiotensin system being slight or lacking. 3 Gastrin release and acid secretion produced by litorin was more rapid in onset but less intense and less sustained than that elicited by bombesin. The same could be observed for pancreatic secretion. 4 Gall bladder contraction stimulated by litorin was probably caused by a double action of the peptide, directly on the bladder smooth muscle, and indirectly by cholecystokinin release. 5 In its effects on the myo-electric activity of the dog duodenum (inhibition of spikes and increase in frequency of pacesetter potentials leading to the appearance of a sequence of slow and small potentials) litorin possessed approximately 50 to 70% of the activity of bombesin.
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PMID:Parallel bioassay of bombesin and litorin, a bombesin-like peptide from the skin of Litoria aurea. 120 79


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