Recent advances in the physiology of gastrin.

Abstract

On 18 May 1905 there was presented at a meeting of this Society a paper in the name of John Sydney Edkins entitled ‘On the chemical mechanism of gastric secretion’ (Edkins 1905). It described experiments in which simple aqueous extracts of antral and fundic mucosa were tested for their power to stimulate gastric secretion when injected as single intravenous doses into anaesthetized cats. Antral extracts excited a secretion of acid and pepsin; fundic extracts did not. Edkins concluded that certain cells in the antral mucosa contained a principle which he named ‘gastrin’; this, he considered, entered the circulation during gastric digestion and stimulated the fundic glands to further activity following on the initial vagal reflex excited by the eating of the meal. These experiments, later recounted in detail (Edkins 1906) initiated more than 40 years of controversy as to the existence of a gastric antral hormone. When attempts were made to confirm and extend Edkins’s observations it was soon discovered that a stimulant of gastric acid secretion could be found not only in antral mucosa but also in many other tissues; and when eventually this ubiquitous agent was identified as histamine (Barger & Dale 1910; Dale & Laidlaw 1910; Popielski 1919) it was widely concluded that the activity of Edkins’s antral extract was due to the presence in it of this substance. The situation was further confused by the failure of apparently well-designed attempts to prove by physio­logical experiment that an antral hormonal mechanism existed, whatever the nature of the hormone. For example, Ivy & Whitlow (1922) and Priestley & Mann (1932) provided dogs with fundic and antral pouches and irrigated the latter with solutions regarded at the time as likely to cause a release of the hormone; but no response from the fundic pouch could be detected, and many years elapsed before the probable reason for such failure became appreciated.