Effects of antrectomy and proximal duodenectomy on duodenal G-cell activity and proliferation in the rat.

The role of the antrum and duodenal bulb in gastrin regulation was investigated in 60 white rats, submitted to 1) simple laparotomy, or 2) antrectomy, or 3) antrectomy with additional removal of the duodenal bulb (1.5 cm). Serum gastrin levels 3-4 months after surgery were repeatedly measured with radioimmunoassay in fasted and in freely fed rats. The duodenum was thereafter removed and its proximal third used to assess the number and cytoplasmic granule content of duodenal G-cells. Basal serum gastrin levels were significantly increased by antrectomy, but reduced by additional resection of the duodenal bulb. Antrectomy, with or without proximal duodenectomy, completely abolished the gastrin response to feeding. Duodenal G-cell density was increased following antrectomy, but the phenomenon was not further enhanced by additional removal of the duodenal bulb. No significant changes in the patterns of gastrin granule maturation were found after antrectomy and proximal duodenectomy.