Background: Impaired gallbladder emptying is a pathogenetic factor in gallstone formation. To test whether gallbladder motility can be improved by high-dose cholecystokinin (CCK), gallbladder emptying was measured sonographically in 21 patients with cholesterol gallstone disease and 6 healthy controls.
Methods: The effects of CCK infusions of 0.06 IDU/kg.min (group A, n = 11) and 0.12 IDU/kg.min (group B, n = 10) were compared with the response to a standard CCK infusion (0.02 IDU/kg.min). Controls received CCK at all infusion rates.
Results: The ejection fraction was smaller after CCK infusion of 0.06 IDU/kg.min than after the standard stimulus (group A, 52 +/- 10 versus 64 +/- 10%, p < 0.05; controls, 66 +/- 10 versus 91 +/- 3%, p < 0.05). After infusion of 0.12 IDU/kg.min CCK ejection fractions decreased even more (group B, 44 +/- 16 versus 65 +/- 12%, p < 0.05; controls, 54 +/- 12 versus 91 +/- 3%, p < 0.05). High-dose CCK infusions shortened the ejection period markedly, whereas the ejection rate remained unaltered.
Conclusions: High-dose CCK does not improve gallbladder motility but blocks the ejection process early, leading to reduced gallbladder emptying in gallstone patients and healthy subjects.