In a total of 117 subjects with a normal histological picture of the fundic mucosa and different bioptic findings of the antral mucosa, quantitative analyses of gastric basal and maximally stimulated secretion were carried out. The statistical analysis showed that basal and maximal secretion are significantly decreased in isolated atrophic gastritis of the antrum compared to normal mucosa and various degrees of superficial gastritis of the antrum. The clinical importance of the isolated antral gastritis is emphasized. A ‘blind’ biopsy of the mucosa of the gastric fundus is inadequate when the diagnosis of gastritis is to be confirmed.