Direct effects of cholecystokinin on human gastric motility.

For a precise analysis of the cholecystokinin (CCK 8) effects on human stomach, we dissected strips of longitudinal and circular muscle from the fundus, corpus and antrum, and circular muscle from the inner and outer pyloric sphincter and duodenum. Specimens were taken during gastrectomy and from stomachs of kidney donors. Mechanical activity was simultaneously recorded under auxotonic conditions. After CCK 8 application, the following effects were observed: (1) direct excitatory effects of CCK 8 with great regional variations in quality and intensity; (2) increases in amplitude of phasic contractions in the outer plyorus and longitudinal antrum (in the other types of preparations the effects were negligible; (3) increases in tonic activity in preparations of the proximal stomach and in strips of longitudinal muscle form the antrum, and (4) remarkable interindividual differences, with negligible responses in one third of the 24 human stomachs examined.