The Histamine Content of Human Gastric Juice after Pentagastrin and Insulin Stimulation

The quantity of histamine entering gastric juice has been followed during standard intramuscular pentagastrin tests in 10 patients (six duodenal ulcer, one gastric ulcer and three nonulcer dyspepsia), and during standard insulin tests in three (all duodenal ulcer). Following pentagastrin, peak histamine output occurred from 0-15 min in six patients and from 15-30 min in two. Acid output peaks followed the histamine peaks by 15 min in four patients, by 30 min in two and by 45 min in one; in one patient the peaks coincided at 15-30 min. In two patients acid output peaks were not preceded by increases of histamine output. Following insulin, acid output peaks occurred at 45-60 min in one patient and at 75 to 90 min in two. In all three patients acid secretion occurred without a significant preceding increase of histamine output. Overall, the results show that, after pentagastrin, histamine is released into gastric juice and the release precedes the peak acid output. After insulin there is no such release. The results are compatible with the hypothesis that pentagastrin acts via histamine in stimulating acid secretion.