Effect of restraint on gastric acidity in the rat

1962 ◽  
Vol 202 (4) ◽  
pp. 812-814 ◽  
Author(s):  
David A. Brodie ◽  
Richard W. Marshall ◽  
Oscar M. Moreno
Keyword(s):  
Gastric Secretion ◽  
Acid Concentration ◽  
Gastric Content ◽  
Free Acid ◽  
Acid Output ◽  
Important Change ◽  
Gastric Fistula ◽  
Total Acid ◽  
Chronic Fistula ◽  
Collection Period

Chronic gastric fistula rats were prepared by implanting stainless steel cannulas in the rumen portion of the stomachs of male Holtzman rats and gastric content was collected in both the unrestrained and restrained state. Gastric secretion in acute pylorus-ligated rats, unrestrained and restrained, was studied at the same time. Volume of gastric content, free and total acidity, and free acid output were significantly lower in the chronic fistula rats as compared to the pylorus-ligated rats in the initial 4-hr collection period. A study of 24-hr gastric content in chronic fistula rats showed that restraint produced a significant decrease in volume, a significant increase in free and total acid concentration, and no change in free acid output, while the restrained pylorus-ligated rats had a significant decrease in volume, no change in free or total acid concentration, and a significant decrease in free acid output as compared with control values. This suggests that an increase in acid concentration is an important change produced in gastric secretion by restraint stress.

Effect of total adrenalectomy on gastric secretion in chronic gastric fistula rats

1964 ◽  
Vol 206 (6) ◽  
pp. 1309-1314 ◽  
Author(s):  
S. P. Bralow ◽  
S. A. Komarov ◽  
H. Shay
Keyword(s):  
Gastric Secretion ◽  
Parietal Cell ◽  
Free Acid ◽  
Acid Output ◽  
Cell Mass ◽  
Chloride Concentration ◽  
Sham Operation ◽  
Gastric Fistula ◽  
Total Acid ◽  
Total Chloride

Basal gastric secretion of rats with chronic fistulas was studied before and after adrenalectomy or sham operation. A marked exponential fall in concentration and output of free and total acid resulted in virtual anacidity within 3–7 weeks following adrenalectomy. Failure in parietal cell secretion was not accompanied by significant decrease in parietal cell mass. Pepsin concentration and output as well as volume also fell exponentially but more gradually. No significant change in total chloride concentration occurred. Relative influence of concentration in determining output was 30 times greater than volume for free acid, 3 times greater for total acid, and twice as great for pepsin. Volume was responsible for almost all variability in total chloride output. Time after adrenalectomy influenced variability of volume and acid output twice as much as concurrent decrease in body weight.

Fasting gastric content of the squirrel monkey (Saimiri sciurea)

1963 ◽  
Vol 204 (4) ◽  
pp. 681-685 ◽  
Author(s):  
D. A. Brodie ◽  
R. W. Marshall
Keyword(s):  
Gastric Juice ◽  
Squirrel Monkey ◽  
Acid Concentration ◽  
Gastric Content ◽  
Free Acid ◽  
Squirrel Monkeys ◽  
Total Acid ◽  
Significant Fall ◽  
Gastric Contents ◽  
Saimiri Sciurea

Free acid was found in the fasting gastric contents of each of 13 squirrel monkeys studied. A comparison of gastric contents from unrestrained and restrained monkeys indicated that restraint significantly increased the free acid concentration. Over a 24-hr period, there was a decrease in volume, free acid and total acid concentration, and pepsin value of the gastric juice. Histamine (0.1 mg/kg hr, subcutaneously) produced a significant increase in free acid and total acid concentration, while the volume and pepsin values were not changed. Methacholine, at cumulative doses of 1.0 and 2.0 mg/kg, subcutaneously, produced a significant decrease in free and total acid concentration while the volume was not altered. Atropine, in cumulative doses of 8, 16, and 48 mg/kg, intraperitoneally, produced a significant fall in volume of gastric juice collected. However, free acid concentration was reduced only at the highest dose and total acid concentration was not changed by any of the doses tested.

Augmented vagal release of antral gastrin by 2-deoxyglucose after fundic vagotomy in dogs.

1979 ◽  
Vol 236 (2) ◽  
pp. E173
Author(s):  
B I Hirschowitz ◽  
R G Gibson
Keyword(s):  
Intravenous Injection ◽  
Serum Gastrin ◽  
Acid Output ◽  
Cholinergic Receptors ◽  
Gastric Fistula ◽  
Gastrin Release ◽  
Total Acid ◽  
Muscarinic Cholinergic Receptors ◽  
Single Intravenous Injection ◽  
Muscarinic Cholinergic

To study the relation between gastrin released by vagal excitation and the secretion of H+ and pepsin under various conditions, central vagal excitation was induced by 2-deoxyglucose (2DG) in doses of 50, 100, and 200 mg/kg body wt given as a single intravenous injection in seven gastric fistula dogs, three with fundic vagotomy and four with intact vagi. Serum gastrin increased linearly with dose doubling in both groups but was twice as high in the vagotomized dogs. Total acid output for 3 h was related linearly to integrated gastrin output in both groups, but the slope, H+/gastrin, was 10 times steeper in the vagally intact dogs (330 vs. 34 mueq/pg gastrin-ml-30 min) and pepsin output almost 20 times greater [5,400 peptic units (PU) vs. 296 PU]. Acidification of the antrum to pH 1.2-1.4 eliminated the gastrin response to 2DG in both groups of dogs. Atropine (100 microgram/kg iv) reduced serum gastrin in the vagotomized and increased it in the intact dogs. Atropinization uncovers stimulation by 2DG by pathways that do not involve muscarinic cholinergic receptors. Stimulation by both pathways is suppressible by acid. We conclude that fundic vagotomy removes an inhibitor of vagal gastrin release.

scholarly journals Effects of the amount and type of food eaten on secretion from fundic abomasal pouches of sheep

1974 ◽  
Vol 32 (2) ◽  
pp. 375-387 ◽  
Author(s):  
L. M. McLeay ◽  
D. A. Titchen
Keyword(s):  
Gastric Secretion ◽  
Acid Concentration ◽  
Dry Matter ◽  
Acid Output ◽  
Pyloric Antrum

1. The effects on gastric secretion of altering the amount and type of food eaten were examined in sheep with fundic abomasal pouches and in sheep which also had the antral region of the abomasum isolated into a pouch or removed (antrectomy). Secretion, which was continuous in all preparations, was collected over 24 h periods, and daily determinations of its acid and pepsin concentrations were made for periods of up to 10 weeks.2. Experimental diets consisting of chaffed lucerne, meadow and wheaten hays were fed on ad lib. or restricted regimens.3. Raising and lowering the dry matter (DM) intakes of lucerne chaff increased and decreased respectively the volume, acidity and acid and pepsin outputs (volume x concentration of acid or pepsin) of fundic pouch secretion.4. Increases of 27–64% in the amount of lucerne chaff eaten, after changing from restricted to ad lib. feeding, were followed by increases in the volume (19–66%), acid concentration (4–10 mequiv. H+/l, 3–9%) and acid output (18–76%) of pouch secretion.5. With DM intakes of mixed lucerne and wheaten chaffs between 88 and 107% of those of lucerne, the secretion from the pouches was reduced to 45–88% of the volume and 39–77% of the acid output observed with the lucerne diet. Acid concentration was least affected, being unchanged in one series of observations and decreased by, at the most, 13 mequiv. H+/l (12%) in another. Reverting to a diet of lucerne chaff reversed these effects: the volume was increased by 30–49%, acid concentration by 2–15 mequiv. H+/l (2–14%), acid output by 38–68% and pepsin output by 30–43% although the intake of DM was the same or 6% less than that on the wheaten chaff mixture.6. Secretion was greater when animals ate lucerne chaff than when they ate meadow chaff.7. The changes in secretion according to diet were obtained in animals with antral pouches and antrectomy as well as in those with only fundic pouches.8. It is argued in discussion that the markedly different abomasal secretions on different diets arise from abomasal stimulation due to the nature rather than the amount of digesta entering it and that although the pyloric antrum contributes to these changes it is not essential for their occurrence.

Effect of restraint on fasting gastric content of spider monkeys

1963 ◽  
Vol 205 (6) ◽  
pp. 1093-1095 ◽  
Author(s):  
Frank P. Brooks ◽  
Peter Ridley ◽  
Francoise Attinger ◽  
Kent Neff
Keyword(s):  
Acid Concentration ◽  
Gastric Content ◽  
Marked Decrease ◽  
Free Movement ◽  
Spider Monkeys ◽  
Total Acid ◽  
Daytime Activity

The effect of restraint in a chair, compared to conditions permitting free movement, on the fasting gastric content was studied in spider monkeys during 3- and 24-hr experiments. In the 3-hr experiments, the volume and "free" and total acid concentrations were significantly reduced during restraint. The pepsin concentration was increased but not to a statistically significant level. In the 24-hr experiments, there was little change noted in volume and acid concentration throughout the study when the animals were restrained. In contrast the freemoving animals showed a greater volume during the period of daytime activity than when they were restrained, but exhibited a marked decrease in volume and acid concentration during the night. The pepsin concentration during the first 9 hr was significantly greater in the restraint experiments.

Response of the Chronic Gastric Fistula Rat to Histamine

1957 ◽  
Vol 190 (2) ◽  
pp. 221-228 ◽  
Author(s):  
Ardelle Lane ◽  
A. C. Ivy ◽  
Emma K. Ivy
Keyword(s):  
Body Weight ◽  
Gastric Secretion ◽  
Free Acid ◽  
The Body ◽  
Threshold Dose ◽  
Maximum Output ◽  
Gastric Fistula ◽  
Average Maximum ◽  
Pharmacological Studies ◽  
Control Output

The preparation of chronic gastric fistula rats, their care and how they may be used for physiological and pharmacological studies on gastric secretion is described. The rat has a large interdigestive secretion and secretes free acid (pH 4.5) after 48–72 hours of fasting. For controlled studies this requires the replacement of fluid and chlorides. Statistically significant differences between the control output of acid and the response to 1 mg of histamine diphosphate were obtained. The threshold dose of the diphosphate is approximately 0.1 for a 350-gm rat. The least amount of histamine diphosphate to yield an average maximum output of acid (10 mg/hr.) is 0.5 mg subcutaneously every 15 minutes. The body dose of histamine required to stimulate gastric secretion is about the same in man, dog, cat and the rat. On the basis of body weight, the amount of histamine base required to yield a maximum output of acid in the rat is 34.6 µg/kg/min. as compared with 1.6 µg/kg/min. in the dog.

Relationship between gastric secretion and behavior in chronic fistula rats

1963 ◽  
Vol 205 (2) ◽  
pp. 230-234 ◽  
Author(s):  
S. A. Komarov ◽  
S. P. Bralow ◽  
H. Shay ◽  
E. Boyd
Keyword(s):  
Linear Regression ◽  
Gastric Secretion ◽  
Linear Correlation ◽  
Gastric Fistula ◽  
Chronic Fistula ◽  
Arbitrary Rank ◽  
Observation Volume ◽  
Significant Linear Correlation ◽  
And Behavior ◽  
Behavior Index

Variations in several parameters of basal gastric secretion and in the behavior index determined in arbitrary rank units were studied in three groups of rats with chronic gastric fistula. There was an impressive similarity between the groups particularly in the patterns of variation during the 6 hr of observation. Volume and outputs of acid, pepsin, and chloride tended to decrease; a negative linear regression on hours was always significant but significant concave up parabolas often better fitted the data. Concentrations of acid and chloride increased significantly during an average experiment either linearly or in conformity with concave down parabolas. Lower concentrations of acid and chloride occurred concomitant with increases in volume and were considered due to salivary contamination associated with a higher behavior index. All above variations in secretion exhibited a significant linear correlation with variations in behavior index. Pepsin concentrations tended to decrease but were not significantly associated with behavior index. As a rule, there were significant differences among animals within groups, but none among the means of replicate experiments.

Cephalic Phase of Gastric Secretion in the Rat

1957 ◽  
Vol 192 (1) ◽  
pp. 23-26 ◽  
Author(s):  
T. M. Lin ◽  
R. S. Alphin
Keyword(s):  
Gastric Secretion ◽  
Gastric Juice ◽  
Free Acid ◽  
Acid Output ◽  
Esophageal Fistula ◽  
Depressing Effect ◽  
Gastric Glands ◽  
Sham Feeding ◽  
Cephalic Phase ◽  
Bilateral Vagotomy

Nineteen sham-feeding tests were performed on eleven rats with a chronic gastric and esophageal fistula. As compared with man and the dog, a slight increase in acid output occurred in 17 tests, the increase being quite definite in 13 tests. Sham feeding had no effect on gastric secretion in 16 tests on rats when performed from 1 to 14 days after bilateral vagotomy. The vagotomy had a profound depressing effect on the interdigestive secretion, no free acid being found in the fasting secretion in any of the rats during the period of these tests. The vagi exert a marked secretory tone on the gastric glands, but the conditioned secretion of gastric juice is probably not of much physiological significance in the rats studied in these tests.

Vagotomy confined to the acid-secreting mucosa of the stomach

1987 ◽  
Vol 73 (1) ◽  
pp. 25-30
Author(s):  
E. P. Dewar ◽  
N. S. Williams ◽  
M. F. Dixon ◽  
D. Johnston
Keyword(s):  
Gastric Secretion ◽  
Myenteric Plexus ◽  
Acid Output ◽  
Gastric Wall ◽  
Neural Tissue ◽  
Gastric Fistula ◽  
Gastric Acid Output ◽  
Before And After ◽  
Acid Secreting ◽  
Gastric Musculature

AbstractChemoneurolysis, using varying concentrations of ethyl alcohol, was performed in dogs with a total gastric fistula in an attempt to denervate selectively only the acid-secreting mucosa, leaving the muscle innervated. Tests of gastric secretion and histological examination of gastric wall biopsies were performed both before and after chemoneurolysis. Chemoneurolysis resulted in a significant reduction in the number of parasympathetic fibres in the submucosa (p<0.01) and a decrease in insulin and pentagastrin stimulated acid secretion. The appearances of the myenteric plexus and gastric musculature were unchanged. The destruction of the submucosal neural tissue was, however, insufficient to produce a th erapeutically significant decrease in gastric acid output.

Preparation of chronic denervated gastric pouches in the rat

1959 ◽  
Vol 197 (2) ◽  
pp. 257-259 ◽  
Author(s):  
R. S. Alphin ◽  
T. M. Lin
Keyword(s):  
Free Acid ◽  
Acid Output ◽  
Gastric Pouch ◽  
Volume Flow ◽  
Gastric Fistula ◽  
Rat Stomach ◽  
Basal Secretion ◽  
Dog Food ◽  
Surgical Preparation

A method is described for the surgical preparation, feeding and care of a chronic denervated gastric pouch in the rat. The basal secretion of the denervated pouch is approximately 0.24 ml/hr. and the hourly free HCl output is nearly zero after a fast of 12 hours. The volume of secretion and the free HCl output both increased after feeding with 3–5 gm of canned dog food. Insulin, 0.5 u, stimulated the output of free HCl from the innervated total gastric fistula but failed to stimulate the volume flow or the acid output of the denervated pouch. A denervated pouch prepared from the squamous or nonglandular portion of the stomach was also described. This portion of the stomach never secreted any free acid at any time over a period of 6 months postoperatively. This is the first physiologic proof that the white portion of the rat stomach is nonacid secreting. The advantages of using a denervated gastric pouch for physiologic and pharmacologic studies are discussed.

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