Gastrin is a gastrointestinal (GI) peptide that possesses potent trophic effects on most of the normal and neoplastic mucosa of the GI tract. Despite abundant evidence for these properties, the mechanisms governing gastrin-induced proliferation are still largely unknown. To elucidate the mechanisms by which gastrin might influence mitogenesis in gastric adenocarcinoma, we analyzed its effects o...

The effect of circulatory transit of the gastric fundus on serum levels of endogenous gastrin measured directly by radioimmunoassay has been studied in 14 dogs. Gastrin was measured in samples obtained simultaneously from the arterial inflow and venous outflow of the gastric fundus. During basal conditions, transit of the gastric fundus resulted in no change in gastrin concentration. During per...

The effect of gastrin on the migrating motility complex (MMC) was studied in seven healthy subjects. It was hypothesized that a potential effect of gastrin on the MMC may result from intraluminal acidification through increased gastric acid secretion. Therefore, antroduodenal manometry and intraluminal acidity were recorded simultaneously. The effect of gastric acid inhibition, with and without...

The effect of an intravenous injection of secretin on plasma gastrin concentration is shown to be dependent upon the relative concentration of the major forms of immunoreactive gastrin present in the plasma at the time of injection. Secretin suppressed gastrin secretion in the fasting state in patients in whose plasma heptadecapeptide and big gastrins predominated and did not suppress when big ...

Proforms of gastrointestinal peptides are cleaved at paired basic residues into intermediate forms. Paired basic residues at the C-terminal then are excised by carboxypeptidases before the peptide is amidated. An obese mouse, called Cpe(fat)/Cpe(fat), has a missense mutation in carboxypeptidase E (CPE) with no pancreatic CPE activity and a reduced processing of pancreatic proinsulin to insulin....

Basal circulating levels of gastrin, somatostatin, and pancreatic polypeptide were measured in 30 chronic haemodialysis patients. Five patients had considerably raised serum gastrin (greater than 400 pmol/1) and also gastric achlorhydria while 75% of the patients who had normal (less than 55 pmol/1) or moderately increased (less than 400 pmol/1) serum gastrin had raised maximal acid outputs. Pa...

Sera from 15 patients with the Zollinger-Ellison syndrome were subjected to gel filtration on Sephadex G-50 superfine columns (10 x 2000 mm). The concentration of gastrin in the effluent was determined by a sensitive radioimmunoassay. Immunoreactive gastrin was eluted in four components in 14 sera. (1) Component I, eluted in the same position as proinsulin, constituted 9.7 +/- 1.2 (mean +/- SEM...

The serum gastrin responses and the integrated gastrin responses to eating three meals of very different composition were studied in the same normal subjects on different days. Two meals, a milk meal of 500 ml, and a breakfast of eggs, toast, butter, marmalade, fruit juice and coffee, were eaten at breakfast time. The serum gastrin responses to these meals were compared and contrasted with the ...

The mechanism of action of gastrin was investigated using cytochemical quantitation of hydroxyl ion production (HIP) in guinea pig gastric oxyntic mucosa. The reaction depends upon the trapping of OH ions produced during gastric stimulation and is blocked by the benzimidazole, Hassle 149/94, which inhibits the K+ + H+-ATPase and by acetazolamide, an inhibitor of carbonic anhydrase activity. It ...

Recent immunohistochemical findings have indicated the presence of gastrin-releasing peptide in normal and pathological human lungs. Gastrin-releasing peptide is a 27-amino acid peptide isolated from porcine gut which bears considerable carboxyterminal homology with bombesin. We have characterized the gastrin-releasing peptide-like peptides present in a human malignant lung carcinoid tumor by g...