S. A. Komarov

A Permanent Rat Gastric Fistula

Summary A simple technic for preparation of a chronic rumenal fistula in the rat using a specially designed Pavlovs type of cannula is described.

Esophagostomy in the Dog Allowing Natural Feeding

Summary A safe two-stage operative technic is described for establishing an esophagostomy in the dog which permits natural feeding. When required for experimental purposes, a simple procedure allows this esophagostomy to assume, temporarily, the advantages of the standard double-barrelled esophagostomy.

An evaluation of some antacid and antipeptic agents in the prevention of gastric ulceration in the rat

Using a simple method, developed in our laboratory, for producing ulcers in rats, we have evaluated a number of therapeutic agents used in the management of gastric and duodenal ulcer for their ability to protect the rumen against ulcerations and for their antacid and antipeptic action. Included in the study were Sodium Dodecyl Sulfate and colloidal aluminum hydroxide, singly and in mixtures, magnesium aluminum silicate, magnesium oxide, di-basic aluminum aminoacetate, magnesium trisilicate, and sodium bicarbonate. The protection of the rumen mucosa was greatest but not complete with Sodium Dodecyl Sulfate and colloidal aluminum hydroxide used singly. The other agents showed a diminishing protective action in the order in which they have been enumerated above. Sodium bicarbonate was the least effective. When combined in a mixture, Sodium Dodecyl Sulfate and colloidal aluminum hydroxide exhibited synergistic beneficial effects and protected the rumen against ulcerations completely. The practical possibilities of combining these two agents in the treatment of gastric and duodenal ulcer are discussed. Our results accent the importance of pepsin in the development of ulceration. With a pH which is just low enough to allow pepsin to act, severity of ulceration was found to be directly related to the “peptic activity” of the recovered gastric contents and was not dependent upon further variations in acidity or in “pepsin concentration.”

Effect of a gastrin preparation on gastric secretion in chronic fistula rats

ConclusionUpon subcutaneous injection to chronic fistula rats gastrin extract prepared from hog antral mucosa was found to be a highly potent agent in stimulating acidity, volume, and total acid output of gastric secretion. Its potency was not appreciably affected by storage in the frozen state for more than 1 year.No stimulation of pepsin secretion by the gastrin extract was observed.In addition, certain effects were noted which suggested the presence in the extract of material inhibiting volume, total acid output, and pepsin secretion levels. No clues as to the nature or the significance of the inhibitory action were found.

EFFECT OF TOTAL ADRENALECTOMY ON GASTRIC SECRETION IN CHRONIC GASTRIC FISTULA RATS.

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.

Pancreatic Lipase—Determination in Canine Pancreatic Secretion and Human Blood Serum: Relationship Between Lipase and Protein Nitrogen in Canine Pancreatic Juice Secreted in Response to Different Test Meals and Under Different Dietary Regimens

A previously reported method for lipase determination was modified to increase the sensitivity so as to permit application of the method without change to both pancreatic secretion and human blood ...

Protection of Gastric Mucosa of the Rat against Ulceration by Prefeeding with Protein Hydrolysates

Summary The supplementing of an already adequate diet with protein hydrolysates in amounts equivalent to 25% of additional protein produced in rats a marked increase in the resistance of the gastric rumen to peptic ulceration without concurrent changes in the volume, the acidity, or the peptic power of the gastric contents. This protective effect was not accompanied by any significant changes in the rate of growth of these animals as compared with animals on a control diet supplemented with sucrose alone.

Effect of thyroid activity on gastric secretion in adult fistula rats.

Summary1. In the adult rat, I131-induced hypothyroidism did not depress gastric secretion as profoundly as previously reported in young animals.2. While total acidity, pepsin concentration, and pepsin output did decrease significantly, volume of gastric secretion continued to increase during the 31 weeks of observation.3. The increase in volume was due partly to a concomitant increase in body weight.4. Volume, acid concentration, and acid output increased when animals were givenl-thyroxine injections 6 times a week for 12 weeks. These parameters of secretion decreased when cortisone was administered in a like fashion after the animals were made hypothyroid with I131.5. Differences in circulating thyroxine as measured by serum PBI explained only 9–13% of the variations in gastric secretion.6. The data also support the concept of seasonal variation in thyroid activity as determined by PBI levels.