Gastric acid response to graded dose of pentagastrin in duodenal ulcer

: To characterize gastric acid response and its age distribution in the patients with duodenal ulcer (DU), we conducted pentagastrin (PG) dose-response study and calculated maximal response (Vmax-c), half maximal dose of PG (Km-c), and the mean response to 0.22 microgram/kg/hr of PG as percent of highest observed response (SI). The mean values of basal secretion (BAO), Vmax-c, and SI in DU were significantly greater than those of normal subjects (N). The mean values of Km-c were significantly less than those of N. The greater BAO, Vmax-c, and SI, and less Km-c were observed in all age groups of DU. The results indicate that DU patients not only secrete more acid but also are more sensitive to stimulation by pentagastrin than N, and that the characteristics are common in all age groups of DU.