Gastric Juice Samples Research Articles

The identification of urogastrone in serum, saliva, and gastric juice

Urogastrone, a peptide isolated from human urine, is known to cause inhibition of gastric acid secretion and proliferation of fibroblasts in culture; furthermore immunofluorescent localization techniques show it to be present in submandibular and Brunner's glands. Serum, saliva, and gastric juice samples have now been fractionated upon Sephadex G-200 and G-50 and the immunoreactive urogastrone located using a specific radioimmunoassay. Biologic activity was shown by mitogenic studies with 3T6 firoblasts. In serum, the major immunoreactive component was ca. 1–2 × 105 daltons, but trypsin treatment then gave a smaller biologically active species in the same position as pure urogastrone on Sephadex G-50. Both saliva and gastric juice showed major components at the position defined by urogastrone, and these also stimulated the uptake of [3H]thymidine into the fibroblasts. It is concluded that a urogastrone-like molecule can be released enzymically from a high molecular weight serum precursor and that the small biologically active peptide is also a normal component of saliva and gastric juice.

The quantification in human gastric juice of duodenogastric reflux by sodium output and by bile-labelling using indocyanine green.

Ten minute samples of gastric juice were collected by naso-gastric aspiration during maximal histamine stimulation in 14 subjects (6 normal, 8 with duodenal ulceration). In eight of these studies, a simultaneous intravenous infusion of Indocyanine green (ICG) was used to label the bile. A single intravenous injection of Boots secretin was given during the maximal plateaux, and further samples collected.

Vitamin B12 Production by the Gastro‐intestinal Microflora of Baboons Fed either a Vitamin B12 Deficient Diet or a Diet Supplemented with Vitamin B12

The vitamin B12‐producing capacity of micro‐organisms isolated from baboon faeces and gastric contents was measured using Lactobacillus leichmannii. The animals were fed either a diet deficient in or supplemented with vitamin B12 (controls). Samples of gastric and small intestinal contents, obtained at laparotomy from two young vitamin B12‐deprived baboons, contained varying quantities of vitamin B12. Many of the organisms isolated from these aspirates produced vitamin B12in vitro. The highest levels of vitamin B12 were produced by anaerobic organisms. Gastric juice samples from vitamin B12 deprived and control baboons contained similar types of organisms with like vitamin B12‐producing capacity. The vitamin B12 content, pH and total bacterial counts of gastric juice samples aspirated after a 6 h fast from vitamin B12 deprived baboons were not significantly different from those of the control animals. The pH values of gastric juice samples aspirated 18 h after feeding, however, were significantly lower than those of 6 h fasting samples in both groups. The mean vitamin B12 levels in the total volumes of gastric juice aspirated after each fasting period were similar. The possible involvement of the gastrointestinal flora in the vitamin B12 status of the baboon is discussed.

Composition of the alkaline component of human gastric juice: effect of swallowed saliva and duodeno-gastric reflux.

Five patients (four with vitiligo and one with pernicious anaemia) were subjected to the histamine infusion test; there were achlorhydric while the remaining two secreted quite small amounts of acid. [Na+],[Cl-)and[alkali]were determined in the alkaline gastric juice samples (pH greater than 7.0). In order to assess the contribution of swallowed saliva the histamine test was done twice in each patient: (A) with precautions to prevent swallowing of saliva; and (B) with the patient allowed to swallow saliva freely. In each sample reflux of duodenal juice was estimated so that its contribution to the alkaline gastric aspirate could be assessed. Such reflex was absent in one patient, negligible in another, while in the remaining three patients the mean pyloric reflux amounted to no more than 8% of the observed volume. Swallowed saliva had diluting effect on [Na+] and [Cl-] but raised K+ concentration in the alkaline gastric aspirate. The comparison of alkaline gastric juice, free to an appreciable extent of salivary contamination, was shown to be relatively constant. The results are consistent with the two-component hypothesis of gastric secretion.

Cyclic nucleotide activity in gastrointestinal tissues and fluids

Published values of adenosine 3′,5′-monophosphate (cAMP) and guanosine 3′,5′-monophosphate (cGMP) in gastrointestinal tissues and fluids have varied depending upon extraction and purification methods and assay procedures. Cyclic nucleotide levels in a variety of gastrointestinal tissues and fluids from several animal species were measured by the Gilman protein kinase assay for cAMP, and by a radioimmunoassay for cAMP and cGMP. The neutral alumina/Dowex-1-formate column was the most accurate for the preparation of bile and gastric juice samples for the measurement of cAMP and cGMP, as verifled by the use of column blanks, spiked samples, phosphodiesterase treatment, and serial sample dilution. Tissue samples gave consistent results regardless of the various column procedures employed.

Nitrite and thiocyanate in the fasting and secreting stomach and in saliva.

The concentrations of nitrite and thiocyanate in fasting and pentagastrin stimulated gastric juice and in saliva have been examined. Nitrite was found in all of 17 samples of fasting gastric juice, mean 4-9 +/- 1-1 muM. Stimulation of gastric secretion with pentagastrin caused no significant change in nitrite concentration. Thiocyanate was detected in all of 21 samples of fasting gastric juice and the difference in concentration between smokers and non-smokers probably reflects similar differences in saliva. In contrast to the nitrite data there was a significant drop in thiocyanate concentration of gastric juice after pentagastrin from 0-9 +/- 0-1 mM to 0-3 +/- 0-04 mM, suggesting a salivary origin for the thiocyanate in gastric juice. Thiocyanate is a powerful catalyst of nitrosation, which, together with small amounts of nitrite and naturally occurring amines could lead to the intragastric formation of carcinogenic nitrosamines and in certain circumstances be a factor in the aetiology of gastric cancer.

Molecular forms of gastrin in antral mucosa, plasma and gastric juice during vagal stimulation of anesthetized cats.

Gastrin was released by electrical vagal stimulation in anesthetized cats. Antral mucosa, blood and gastric juice samples collected during vagal stimulation were subjected to gel filtration in order to characterize the different molecular forms of gastrin. In antral mucosa component III (gastrin-17) predominated. Besides, the antrum contained 5 per cent component II (gastrin-34, "big" gastrin), 1 per cent component I and trace amounts of component IV (gastrin-14 or "mini" gastrin). Immediately after vagal stimulation, component III (gastrin-17) appeared in the gastric venous effluent followed within a few minutes by component IV (gastrin-14). Component I and II (gastrin-34) were not detectable in any of the plasma samples. We suggest that component III (gastrin-17) is released from the antral mucosa and is then rapidly metabolized to component IV (gastrin-14) possibly to a significant extent in the fundic region of the stomach. Large amounts of component III (gastrin-17) were found in the vagally-induced gastric juice. Only very small amounts of degradation products were present, indicating that cat gastrin is relatively resistant to peptic degradation and acid hydrolysis.

Duodenogastric reflux: a cause of gastric mucosal hyperaemia and symptoms after operations for peptic ulceration.

This study has investigated the possible association between duodenogastric reflux, gastritis, and symptoms in 35 patients with or without dyspepsia one to 15 years after gastric surgery. Five patients were excluded because of biliary disease, hiatus hernia, or recurrent ulceration. The remaining 30 were assessed by a symptomatic score, measurement, of bilirubin and sodium concentrations in samples of fasting gastric juice, endoscopy, gastric biopsy, and the presence of radiological reflux. In 15 patients with a symptom score of less than the median, gastric bilirubin levels were less than 1 mg/100 ml in 80%; severe endoscopic changes were seen in only one patient and reflux was not observed. In contrast, in patients with a symptom score in excess of the median fluoroscopic and biochemical reflux was seen in 69 and 80% respectively and severe mucosal hyperaemia in half. There was a significant correlation between symptoms, gastric hyperaemia, and duodenal reflus ( P smaller than 0-02).

Lysolecithin: a factor in the pathogenesis of gastric ulceration?

Lysolecithin is formed when pancreatic juice and bile mix in the duodenum. Lysolecithin concentrations have been measured in intermittent samples of night gastric juice from patients with gastric ulcers and duodenal ulcers and in normal controls. In gastric ulcer patients, the mean of the peak concentrations (444 mug/ml) and mean of concentrations in all samples (199 mug/ml) were significantly higher than in controls (34 mug/ml and 18 mug/ml respectively). Duodenal ulcer patients had normal or moderately raised values. The levels in gastric ulcer patients were as high as those which have been found experimentally to cause severe damage to the gastric mucosal barrier, and it is concluded that lysolecithin may be as important, or more important, than bile salts in the destruction of the gastric mucosal barrier and therefore in the aetiology of gastric ulcer.

Presence of prostaglandins E 2 and A 2 in canine gastric secretions

The presence of prostaglandins (PGs) was determined in gastric juice obtained from 3 conscious dogs, provided with a chronic gastric fistula. Outputs of acid (mequiv min −1) and PGs (pg min −1) were measured in gastric secretions stimulated by pentagastrin (100 or 200 ng kg −1min −1). Prostaglandin activity was estimated, after extraction and thin layer chromatography, by radioimmuno-assay of the PGB formed by treatment with alkali. Tritiated PGs were added to gastric juice for the purpose of correcting for PGs recovery. Using this method, the minimum mass of PGB which could be satisfactorily distinguished from zero was 25 pg. Prostaglandins A 2 and E 2 were present in pentagastrin-activated gastric secretions and averaged (mean ± SE, n = 8) 200.7 ± 18.1 and 260.1 ± 18.0 pg min −1 respectively. The identity of PGA 2 and PGE 2 was confirmed by gas liquid chromatography combined with mass spectrometry. The amount of PGE 2 converted to PGA 2 during extraction, separation and conversion procedures was estimated from the amount of [ 3H] PGA 2 found when only [ 3H] PGE 2 had been added to a sample of gastric juice and averaged 14.5% ± 2.0. Our preliminary results support the possibility that PGE 2 and PGA 2 may be of physiological importance in the regulation of canine gastric secretions.

Pyloric reflux: a modification of the two-component hypothesis of gastric secretion.

1. Gastric juice was obtained during continuous maximal stimulation with histamine diphosphate, 0.13 μmol h−1 kg−1 (0.04 mg h−1 kg−1) intravenously, in thirty-four control subjects, twenty-eight patients with duodenal ulcer, and eighteen with gastric ulcer. After correction for pyloric losses, the average rate of outputs of water, and of H+, Na+, K+ and Cl− were determined. 2. The results were analysed in terms of the two-component theory of gastric secretion. The acid components in control subjects and duodenal ulcer patients were similar in composition, but that in gastric ulcer patients was by comparison hypotonic and less acid and contained more sodium ions. 3. Calculation of the volume and composition of the alkaline component gave reasonable results in the control and duodenal ulcer groups, but impossible results in the gastric ulcer group. The gastric juice of gastric ulcer patients could not be described in terms of classical two-component theory. 4. In all three groups, volume correlated quite well with Cl− output alone, less well with H+ output, poorly with K+ output, and not at all with Na+ output. However, when volume was expressed as a function of the outputs of Cl− and one other ion, K+ performed poorly, H+ well, and Na+ best of all. 5. Some features suggest that reflux of alkaline liquid from the duodenum is a better explanation of these results than back-diffusion of H+ in exchange for Na+ between the lumen and wall of the stomach. 6. If the refluxing liquid is assumed to be isotonic, its composition can be calculated. Hence, the volume of reflux in a sample of gastric juice can be deduced. Reflux appeared to be more important in the gastric ulcer patients than in the other two groups.

Poly- and disaccharidases in Vespa orientalis (Vespinae: Hymenoptera)

1. 1. Carbohydrate hydrolases (Group 3) of Vespa orientalis were quantitatively assayed. 2. 2. In most body tissue homogenates and fluids maltase and sucrase were the most active disaccharidases. 3. 3. Trehalase was the most active in all venom samples and in the gut of workers. 4. 4. Isomaltase activity was lower than the other three major disaccharidases and it was absent from the head of adult insects and from larval fat body. 5. 5. Lactase and cellobiase activity was only found in hemolymph, gut and gastric juice samples. 6. 6. Polysaccharidase activity was present in all of the examined samples. 7. 7. Stored hemolymph samples (−20°C) had high initial glucose levels, but no significant difference was found in the enzymatic activity between stored and fresh hemolymph. 8. 8. Anaerobic conditions did not prevent or delay glucogenesis in fresh hemolymph.

HUMORAL AND CELL-MEDIATED INTRINSIC-FACTOR ANTIBODY IN PERNICIOUS ANEMIA

Lymphocytes from 86% of patients with pernicious anæmia showed evidence of cell-mediated immunity against intrinsic factor. Humoral intrinsic-factor antibodies were present in the serum from 53% of these patients, and in gastric-juice samples from 54% of patients. There were no such antibodies in samples from matched controls. All but 1 of the 25 patients with pernicious anæmia in whom all three tests were carried out had intrinsic-factor antibodies. It is concluded that there were autoimmune factors against intrinsic factor in virtually all patients with pernicious anæmia, and that the disease did not develop in the absence of such antibodies.

Relation Between Hydrogen Ion Secretion and Oxygen Consumption by Ex Vivo Isolated Canine Stomach, Perfused with Homologous Blood

The relationship between oxygen consumption and acid secretion was studied in 28 totally isolated ex vivo canine stomachs, perfused extracorporeally with homologous blood. Two hundred six 30-min samples of gastric juice and blood were collected for biochemical analysis. Paired values of HCl (microequivalents per minute) and O2 consumption (micromoles per minute) were then analyzed by the method of least squares, using a computer. Linear correlation was calculated between these two values. The correlation coefficient was 0.9518 and the slope of the line was 0.512. The ratio of hydrogen ions produced to oxygen molecules consumed was 1.18 ± 0.53. The range of titratable H+ found in this study was from 0 to 833 μequiv/min and the range of O2 consumed was from 18 to 442 μmol/min.

The Managerial Revolution

AIM--To study the effect of known interference in the measurement of urea and ammonium concentrations in samples of gastric juice. METHODS--The effect of pH and ammonium concentration on the o-pthalaldehyde method, the diacetylmonoxime method, a Berthelot linked method and an enzymatic urease method for the measurement of urea in gastric juice was therefore conducted. An enzymatic method of the measurement of ammonium in gastric juice was also assessed. RESULTS--The o-pthalaldehyde and the enzymatic urease methods were unaffected by a low gastric juice pH, ammonium concentrations of 10 mmol/l, and had interassay coefficients of variation of 3.9-5.6% and 2.8-10.6%, respectively, over a urea concentration of 2.5 mmol/l-20 mmol/l. The Berthelot linked method resulted in low gastric juice urea concentrations. The enzymatic method of ammonium measurement also proved suitable when the effect of low gastric juice pH was controlled. CONCLUSION--Interference by low pH did not explain the differences in reports of gastric juice urea or ammonium concentrations.

Gastric secretory and splanchnic blood flow studies in man after severe trauma and hemorrhagic shock

A group of thirty-three patients with severe multiple trauma and hemorrhagic shock and a group of nineteen normal control subjects were studied in a special trauma research unit to determine the effect of severe acute stress on multiple aspects of human gastric secretion and splanchnic blood flow in relation to stress ulceration. Simultaneous studies of gastric acid, pepsin, nondialyzable solids, fucose, sialic acid, and total splanchnic blood flow were carried out on both patients and control subjects. These studies were performed during basal conditions over a period of two hours and also for two hours after subcutaneous injection of Histalog. On the basis of these studies, it was concluded that excessive acid or pepsin secretion or deficient quantitative or qualitative gastric mucus production was probably not a significant etiologic factor in the production of gastroduodenal stress ulceration. The splanchnic blood flow studies and the presence of blood in gastric juice samples after Histalog injection in approximately 35 per cent of the severely injured patients supported previous opinions that ischemic damage to the superficial gastric mucosa may induce stress ulceration.

Peptides of normal human gastric juice.

Normal human gastric juice has been examined for the presence of peptides. Five pooled resting samples have been found to contain a decapeptide of low chromatographic mobility. The sequential structure of this peptide was shown by analysis, and by comparison with a synthetic sample, to be Leu‐Ala‐Ala‐Gly‐Lys‐Val‐Glu‐Asp‐Ser‐Asp Two of the gastric juice samples also contained a peptide of slightly higher Rf value in smaller quantity. This second peptide, though not characterized completely, appeared to have the structure of a nonapeptide. The amino acid composition differed from that of the decapeptide in that leucine was absent; alanine was the N‐terminal amino acid. These peptides have not previously been reported to be present in normal human gastric juice. The authors have not observed any of these peptides in a small number of samples from pernicious anaemia patients.

Dissociation of Intrinsic Factor from its Antibody: Application to Study of Pernicious Anaemia Gastric Juice Specimens

Intrinsic factor antibody may sometimes be concealed in the gastric secretions of pernicious anaemia subjects, being complexed with residual amounts of intrinsic factor.A method is described for dissociating intrinsic factor from its antibody. Antibody to the vitamin-B(12)-binding site of intrinsic factor was identified in 16 (57%) out of 28 samples of pernicious anaemia gastric juice after dissociation but in only 10 before dissociation. There was no clear relationship between the incidence of antibody in the serum and in the gastric juice of these patients.

Measurement of Gastric Hydrochloric Acid after Maximal Histamine Stimulation with Special Reference to Achlorhydria

Titration to different pH end points was performed in all samples of gastric juice from 208 patients with gastro- instestinal diseases and healthy persons, examined with the augmented histamine test. Titration to pH 3.3 and to pH 7.0 revealed differences in hydrogen ion concentration, which were significantly negatively correlated to the maximal acid output, calculated from the acidity at pH 3.3. Differences between maximal acid outputs, calculated from the acidities at pH 3.3 and pH 7.0, varied only little in all examined groups with the exception of gastric juice contaminated by food. Titration to pH 7.0 or higher overestimates gastric hydrochloric acid, especially in gastric juice from patients with gastritis and gastric juice contaminated by food. The results of this study support previous investigations, which recommend titration of gastric juice to pH 3.5 with simultaneous measurement of pH. Achlorhydria corresponding to absence of parietal cells is hereby defined by a pH higher than 3.5 and a pH fall less than one pH unit from basal to maximally stimulated values.

DOSE DEPENDENCE OF INSULIN-STIMULATED GASTRIC SECRETION.

The volume; concentrations of H, Na, K and Cl; osmolality; and pepsin concentration of 16 consecutive 15-min. samples of gastric juice were measured and related to venous blood sugar, hemoglobin, and hematocrit, and plasma Na, K, and osmolality in 9 conscious gastric fistula dogs after the I.V. injection of commercial insulin in doses of 0.15, 0.3, 0.6, and 0.9 U/kg. Crystalline (glucagon-free) insulin in doses of 0.15 and 0.6 U./kg. gave essentially identical results.