Evidence that bombesin releases extragastric gastrin in man

Bombesin-induced gastrin release from extragastric sources has been investigated in two groups of patients without gastric antrum: 11 patients with total gastrectomy and 11 patients with subtotal (Billroth II) gastrectomy. A 30-min bombesin infusion (5 ng · kg −1 · min −1) caused a prompt significant gastrin increase ( P < 0.05) in both groups of patients. The gastrin response to bombesin was significantly ( P < 0.005) lower in patients without antral tissue than in the control group ( n = 7). The individual peak gastrin responses, in totally (TG) and subtotally (SG) gastrectomized patients, were significantly over basal levels (TG: peak 100.3 ± 12 vs. basal 62.8 ± 9.1, P < 0.005; SG: peak 96.9 ± 9.4 vs. basal 72.4 ± 6.8, P < 0.001; pg/ml, mean ± S.E.M.). These data indicate that bombesin acts not only on antral G cells, but on all gastrin cells in the gastrointestinal tract.