The histamine-infusion test of gastric acid secretion in man

Lawrie, James H (1969) The histamine-infusion test of gastric acid secretion in man. MD thesis, University of Glasgow.

Abstract

The history of the evolution of tests for gastric acid secretion has been reviewed (Chapter 1), taking particular note of the changing fashions in the form of tests, the slow development of increasingly precise methods of measurement, and the continuing difficulty in deriving substantial information from the results. In this context, the value of the steady state of maximal acid secretion induced by an infusion of histamine, had been acknowledged in experimental work, but had been exploited only to a limited extent in studies in man. Using a slow injection pump and disposable sterile equipment, a technique was evolved whereby this method of stimulation could be used to study large numbers of patients and control subjects. Dose-response curves were determined, and from these the dose-rate of 0.04 mg histamine acid phosphate per kg body weight per hour was shown to elicit a maximal acid response. Using this dose-rate throughout, the responses were calculated to consist of a valid plateau of output, to have an acceptable reproducibility in duplicate tests, and to be consistently greater than any of the established methods of calculating the augmented histamine response (Chapter 2.), The test was, to some extent, self-checking, and radiological monitoring of nasogastric tube position could be obviated. Side effects were tolerable and transient. Many subjects were studied satisfactorily as out-patients. Normal standards were determined (Chapter 3) for volume, concentration and output of acid in 54 men and 50 women. The mean output for the men, 25.3 mEq/hour, was significantly higher than that for the women, 21.7 mEq/hour, This difference was due only to the larger volumes of gastric acid secreted by men, the concentration of acid being similar in both men and women (108.4 and 110.4 mEq/litre respectively). Output declined with age in men, but not in women. There was no relationship with body weight in either men or women. The range of acid output appeared to be similar for both sexes, i.e. 9.5 - 42 and 9.7 - 47.1 mEq/hour in men and women respectively and the possible pathological significance of values out with these ranges is discussed. These methods and standards were applied to the study of various peptic disorders (Chapters 4 - 9). In a group of 31 patients with chronic iron-deficiency anaemia (Chapter 10) 5 were achlorhydric, 9 had a normal acid output and 17 (54%) had abnormally low though measurable acidity. After treatment 7xth iron 7 of the younger patients who had previously some acid secretion, showed an improvement in acid output. Older patients and those already achlorhydric showed no change. In patients with jaundice (Chapter 11), regardless of the diagnosis, almost one-half were achlorhydric, and no correlation was found between acid output and any of the factors customarily associated with liver function. As in the previous group, there were many subjects who secreted very low but measurable amounts of acid. Finally, an attempt was made to assess the synthetic pentapeptide of gastrin (I.C.I. 50,123) (Chapter 12) in conditions precisely comparable with those obtaining for the histamine-infusion tests. Dose-response relationships showed that 5 jag/kg/hour by infusion elicited a maximal response, and this dose-rate was used to compare with the standard histamine-infusion test using 40 pg/kg/hour, in a series of 43 subjects. The mean acid output by histamine v/as 31,5 mEq/hour and by pentagastrin 30,2 mEq/hour, The coefficient of correlation between the two responses (r =; 0,939) was highly significant.

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Additional Information: Adviser: A PM Forrest
• Keywords: Medicine
• Date of Award: 1969
• Depositing User: Enlighten Team
• Unique ID: glathesis:1969-72736
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 11 Jun 2019 11:06
• Last Modified: 11 Jun 2019 11:06
• URI: https://theses.gla.ac.uk/id/eprint/72736