Pertechnetate and the Stomach--a continuing controversy.

Technetium-99m is concentrated by the stomach following intravenous injection. This principle allows the detection of ectopic gastric mucosa and has been used to develop a noninvasive test of gastric secretion. The cellular site of concentration is controversial, however, with evidence implicating both the acid-secreting parietal cells, and the mucus secreting epithelial cells of the gastric mucosa. This evidence is reviewed and appraised. It is suggested that the primary mechanism lies in the mucous cell but that total gastric activity following pertechnetate reflects the health, surface area, and blood flow of the mucous epithelium.