Effect of gastrectomy on gallbladder motility: an experimental study

Abstract

Gallstone formation is frequently seen following gastric surgery. Since dysmotility and bile stasis of the gallbladder is considered as an important factor in the pathogenesis of gallstone formation, altered gallbladder motility due to gastric surgery may have a role in the development of post-gastrectomy gallstone formation. To test this hypothesis, the effect of distal partial gastrectomy on gallbladder motility were studied. Gastroduodenal and gallbladder contractions were recorded by chronically implanted strain gauge transducers under conscious state. Gallbladder volume changes were monitored using chronically indwelling gallbladder catheter. Fasted and fed motility were studied in control (n = 5) and gastrectomized (n = 3) dogs. Plasma concentration of putative hormone CCK was measured. Effect of CCK-OP and motilin on gallbladder emptying were also studied. In fasted state, gallbladder volume was periodically decreased synchronous with phase 3 of interdigestive migrating contractions (IMC) in the gastroduodenum in both group of dogs. The correlation between gastric and gallbladder contractions was preserved even following distal partial gastrectomy, though the frequency of phasic contractions during phase 3 of IMC was decreased in the gastrectomized dogs. Postprandial gallbladder emptying tend to decreased in the gastrectomized dogs, while there were no difference in the postprandial plasma CCK concentrations and CCK-OP induced gallbladder emptying between groups. Digestive period was shortened in the gastrectomized dogs, which resulted in early gallbladder refilling and prolonged interdigestive period. Decreased frequency of gallbladder phasic contractions during IMC and prolonged interdigestive period could cause bile stasis in the gallbladder, which may, in part, explain post-gastrectomy gallbladder formation.