In 12 duodenal ulcer patients, gastric emptying (GE) of a radiolabelled solid meal, gastric acid secretion, and gastrin release were examined before and during the early postoperative period (median 13.5 days) after a highly selective vagotomy (HSV). HSV significantly delayed GE; the median slope of GE curves (K) decreased from 11.86 to 6.52 min-1 x 10(-3) (p < 0.01). A significant inhibition of the late phase of GE was reflected by a diminution of the curve shape parameter (S) from a median of 1.41 to 0.98 (p < 0.02). A profound impairment of GE after HSV was found in 4 of 12 patients (33%). HSV resulted in a 49% decrease in the basal acid output (6.9 +/- 1.0 before to 3.5 +/- 1.0 mmol.h-1 after HSV, and a 56% reduction in the pentagastrin-stimulated gastric acid secretion (31.1 +/- 5.1 before vs 13.8 +/- 2.4 mmol.h-1 after HSV (p < 0.01). A significant increase in both the fasted serum gastrin (38.9 +/- 3.7 to 66.9 +/- 8.4 ng.l-1, p < 0.05) and the meal-stimulated gastrin release (AUC0-120: 7179 +/- 440 to 11158 +/- 1062 ng.l-1 min, p < 0.05) was observed after HSV.