Barbara H. Fenton

Antacid therapy of peptic ulcer Part II An evaluation of antacids in vitro

All the parameters needed to calculate the adequate dose of antacid will probably never be known in most cases of peptic ulcer before treatment; some of the techniques, such as the measurement of emptying rate and starting index, are moderately time-consuming procedures (Hunt and Spurrell, 1951). The basal secretion, however, is known in many, if not most patients, and with knowledge of its value and the observations of other workers on emptying rates and starting indices, an approximation ofthe antacid dosage can be obtained (Fig. 1). If no information at all is available an approximate dose can be determined based on statistical data as in Table II. The calculated doses listed in both the Figure and Table II are those required to neutralize basal secretion and do not take into consideration the secretory response to frequent meals that further increase gastric secretion and consequently the required dose of antacid. It is obvious from Table V that doses of antacid must be given at least hourly if any effect is to be produced by commonly used doses. It is emphasized that while the adequacy of the mathematical model here employed to describe the secretion into and emptying from the stomach is well established in the literature, there is wide variation in the values of the different parameters in various reports (Table 1), and thus the calculated doses of antacid are approximate only. The independence of the half-time of gastric emptying and the starting index, assumed in some calculations above, may not be strictly true and would also affect the calculated antacid dosage. Inadequate mixing of antacid is a further unpredicatable factor influencing the required dose of antacid. Any rhythmic gastric actions would introduce further uncertainties, since for given average basal secretion and emptying rates the dose required would vary according as the time of administration was related to the commencement of the cyclic periods. Notwithstanding these uncertainties, the general agreement in antacid requirement between the study of Price and Sanderson (1956) in vivo and this mathematical study using data from the literature confirms the general validity of the conclusions. It is emphasized that the dosage determined in the above calculations is minimum dosage. The stimulation of gastric secretion by meals would necessitate increased antacid dosage, and it is possible that gastric secretion and emptying may not be independent variables, and those patients with high secretion rates may have rapid emptying rates, thereby increasing dosage of antacid. We believe that the minimum antacid doses are as follows: If no information is available on the patients gastric function, then a dose of 50 mEq. once hourly is adequate for duodenal ulcer in a man, 26 mEq. for duodenal ulcer in a woman or gastric ulcer in a man. If the patients basal secretion rate is known, a dose of neutralizing capacity eight times the secretion rate should suffice in most cases, if given hourly.

The adsorption of pepsin

Summary1. The most powerful adsorbents of pepsin are aluminum hydroxide gel and charcoal.2. The adsorbent action of pepsin is uninfluenced by the substrate concentration and is less active at lowpH levels. When used to inactivate pepsin, the adsorbent effect of aluminum hydroxide gel is more important than thepH effect.3. The capacity of aluminum hydroxide gel to adsorb other substances such as anticholinergic agents and antibiotics should be remembered when it is used in the treatment of peptic ulcer.4. The antipeptic capacity of aluminum hydroxide gel and the secretory responses found in ulcer patients have been discussed in relationship to the dosage used in ulcer therapy.

Isoenzymes of lactate dehydrogenase in human gastric mucosa and gastric carcinoma tissue.

Lactate dehydrogenase (LDH) isoenzymes were demonstrated electrophoretically in human fundic and pyloric gastric mucosae and in gastric carcinoma tissue. Fundic gastric mucosa consistently displayed a pattern with predominance of LD1, LD2, and LD3. Pyloric gastric mucosa and cancer tissue consistently had identical patterns with a predominance of LD2, LD3, and LD4, differing significantly from the LDH isoenzyme pattern of fundic mucosa. The LDH isoenzyme pattern characteristic of fundic mucosa extended very close to the histological junction between body and pyloric gastric mucosa and was not affected by the presence of gastritis in the stomach. These results serve to demonstrate yet another difference between mucosa from the acid-secreting and the pyloric areas of the human stomach.

Protein content of gastric juice Part I A study of the validity of the biuret reaction in determining protein concentration after peptic digestion and acid hydrolysis of protein

EDITORIALSYNOPSISInitially itisdemonstrated thatthebiuret methodisan accurate methodof determining protein concentration whentheprotein hasbeensubjected tovarying degrees ofacid hydrolysis andpeptic digestion. Using continuous gastric suction, andthebiuret methodofmeasuringprotein concentration, theprotein content ofgastric juice ina series ofconditions was determined. Gastric cancerpatients have ahigher basal protein concentration thancontrol subjects and duodenal ulcer patients andgastric ulcer patients have ahigher protein concentration thanduodenal ulcer patients. Instimulated gastric juice, duodenal ulcer patients have alower protein concentration thangastric ulcer andgastric carcinoma patients andcontrol subjects. Thebasal protein outputs were similar inthefour groupsstudied. There was no correlation between theprotein andD.N.A.content ofgastric juice. Theprotein lost into thestomach may varybetween 1 and16g.perday.

EFFECT OF HISTAMINE ON THE PROTEIN AND MUCUS CONTENT OF GASTRIC JUICE.

Summary1. Histamine causes a fall in the concentration of both protein and mucus in gastric juice; the stimulatory effect of histamine on the volume of secretion, however, results in a marked rise in output of protein and a less marked rise in the output of mucus.2. The effect of histamine is more marked on protein secretion than on mucus secretion, and the rise in output of protein cannot be explained by the effect on mucus secretion.

Gastric mucus secretion in normal subjects and patients with gastric ulcer, gastric carcinoma, and pernicious anemia

SummaryThe mucus secretion of a series of patients with gastric ulcer, gastric carcinoma, and pernicious anemia, studied in regard to concentration, output and constituent sugars in basal gastric secretion, showed few differences between the groups of patients. Pernicious anemia patients showed high mucus concentrations due to their low secretory volume. Gastric ulcer patients had a mucus output and concentration similar to control subjects. The only obvious difference in mucus secretion appeared to be that in gastric carcinoma patients; in this group, the amount of glucose in proportion to other sugars was high.

The effect of 10-(β-dimethylaminoproprionyl) phenothiazine methobromide on gastric secretion

SummaryAn anticholinergic and ganglion-blocking drug, 10-(a-dimethylaminoproprionyl) phenothiazine methobromide (Secergan), which is both a quaternary ammonium salt and a phenothiazine derivative has been assessed with regards to its effect on saliva flow and gastric secretion. It was found to have no effect on stimulated gastric secretion in dosages which produced slight but significant depression of saliva flow.

Effect of nitrogen mustard on gastric secretion in the rat

SummaryThe effect of nitrogen mustard on gastric secretion was studied using a pylorus-ligated rat preparation. Nitrogen mustard caused temporary reduction in the volume of gastric secretion and also caused a significant decrease in the output of acid by the rat stomach. The possible causes of these effects are discussed.

ENZYME SYSTEMS IN GASTRIC MUCOSA.

Summary1. Enzymes of the glycolytic and Krebs cycle pathways of glucose metabolism were found in homogenates of gastric mucosa. The enzymes of the hexose monophosphate shunt could be detected, but activities were minimal. Significant activities of alkaline phosphatase, GOT, β-glucuronidase, LAP, ornithine transcarbamylase, and GPT were also present.2. Enzyme activities of GOT, LDH, and PHI were greater in fundic mucosa than in pyloric mucosa, but the pyloric mucosa showed greater β-glucuronidase and GPT activities.