Physiological effect of cholecystokinin on gastric emptying of liquid in functional dyspepsia

Objective : Early satiety and postprandial epigastric fullness are common symptoms in functional dyspepsia. Cholecystokinin (CCK), a mediator of satiety in humans, may be responsible for these symptoms through an increased effect on delaying gastric emptying. Methods : In five normal subjects and in five patients, gastric emptying of inert liquid mixed with technetium (Tc 99m ) was studied during i.v. perfusion of normal saline and of physiological concentrations of CCK octapeptide. Results: Administration of CCK significantly delayed emptying of inert liquid in patients and in normal subjects, and the effect was of similar magnitude in the two groups : residual gastric volumes at 90 min increased from 9.9 ± 6.1 to 32.1 ± 6.2% (p < 0.025) in controls and from 9.8 ± 4.4 to 32.2 ± 4.7% (p < 0.005) in patients during saline infusion in comparison with CCK infusion ; also, prolongation of half emptying time was not different between the two groups (19.4 ± 1.9 min to 39.4 ± 15.2 min in controls and 19.5 ± 3.0 min to 31.4 ± 7.9 min in patients). Conclusions : We conclude that CCK at physiological concentrations acts similarly in normal subjects and in patients with functional dyspepsia; this suggests that, if this hormone is normally released after a meal, a peripheral action of CCK through delayed gastric emptying is not responsible for increased postprandial satiety in functional dyspepsia.