Effect of two-week treatment with enprostil (35 micrograms twice a day) on 24-hour serum gastrin levels.

After a meal, a single dose of enprostil, a synthetic dehydroprostaglandin E2, inhibits gastrin level in both normal subjects and patients with duodenal ulcer, whereas H2 blockers exaggerate the postprandial gastrin response. However, the effect of prolonged treatment with enprostil on the gastrin profile is unknown. The aim of this study was to compare serum gastrin levels over a 24-hr period before (day 0) and on the last day (day 14) of a two-week course of enprostil (35 micrograms twice a day). Nine healthy volunteers (four women and five men), ages 29 +/- 5 years (range 23-39) were studied twice during a 24-hr period. Serum gastrin was measured at 30-min intervals during the day and at 2-hr intervals during the night. Enprostil (35 micrograms) was taken after basal gastrin serum measurement at 8:00 AM and PM. Standardized meals were ingested at 8:30 AM, 12:30 PM, and 8:30 PM. The postprandial integrated serum gastrin response was calculated after the three meals (4-hr period). Fasting serum gastrin levels were similar for the two periods. Integrated postprandial gastrin response was significantly inhibited after breakfast and dinner (P less than 0.001). Average results are expressed as mean +/- SEM (pmol/min/liter). During the night, gastrin levels were significantly decreased by enprostil. After 14 days, the inhibition of gastric acid secretion, which induces an increase of gastrin release with other antisecretory drugs, remained counterbalanced by the antigastrin properties of enprostil.