Effect of partial gastrectomy with Billroth II or Roux-en-Y anastomosis on postprandial and cholecystokinin-stimulated gallbladder contraction and secretion of cholecystokinin and pancreatic polypeptide

This prospective study was undertaken to determine the, effect of partial gastrectomy without vagotomy on postprandial gallbladder contraction and secretion of cholecystokinin (CCK) and pancreatic polypeptide (PP) in 22 peptic ulcer patients randomly assigned to either Billroth II (N=11) or Roux-en-Y (N=11) anastomosis. The patients were studied within two weeks before surgery and at six months postoperatively. After surgery basal gallbladder volumes were larger than preoperatively (P < 0.02). Integrated postprandial gallbladder contraction was not significantly affected by gastrectomy, either in the patients with Billroth II anastomosis (2276±268 vs 1985±362%/60 min) or in those with Roux-en-Y anastomosis (2045±327 vs 2445±352%/60 min) when studied pre- and postoperatively, respectively. Similarly, integrated postprandial plasma CCK secretion was not significantly changed by either Billroth II gastrectomy (200±31 vs 166±21 pM/60 min) or Roux-en-Y gastrectomy (146±26 vs 147±12 pM/60 min). However, integrated postprandial PP secretion was significantly (P < 0.05) lower after Billroth II gastrectomy (6.8±2.4 vs 2.2±1.0 nM/60 min), while the reduction in plasma PP after Roux-en-Y gastrectomy just failed to reach statistical significance (6.0±1.5 vs 3.4±0.9 nM/60 min). Similarly, the PP response, but not the gallbladder response, to an intravenous bolus injection of 1 IDU CCK/kg body weight was significantly decreased after gastrectomy independent of the type of anastomosis. It is concluded that gastrectomy does not affect postprandial plasma CCK secretion and gallbladder contraction, but reduces the PP response to a mixed meal and that these results are not influenced by the type of anastomosis. It is possible that the larger postoperative gallbladder volumes may play a role in the pathogenesis of gallstone disease after gastric surgery.