The method of assaying gastric secretogogues, first described by Ghosh and Schild1 was modified by Lai2 for the assay of gastrin in extracts of gastric antrum and other tissues. This technique was subsequently employed by Sircus3 and by Moore and his colleagues4 for the detection of gastrin-like activity in the serum and gastric juice of patients with the Zollinger-Ellison syndrome. The last-named authors reported a high incidence of positive results and emphasized the reliability of the method in the preoperative diagnosis of such patients. Ellison and Wilson,5 however, were unable, in several instances, to detect a gastric secretogogue in the serum of patients with proven ulcerogenic tumors of the pancreas.
In establishing the bioassay method for gastrin in our laboratory, it was considered necessary to re-evaluate the factors affecting its sensitivity, range, and reliability, using the now available synthetic gastrin pentapeptide. This report is based