Elevated cholecystokinin-like activity in the duodenal mucosa in patients with cholecystolithiasis.

Cholecystokinin (CCK)-like activities in the duodenal mucosa of the patients with cholecystolithiasis were determined with the bioassay method we established. The results obtained are as follows: The gall bladder of the patients with cholecystolithiasis following oral administration of egg yolk has contraction rates comparable to those of the normal subjects in the control group, whereas the contraction rate of the gall bladder of the patients with cholecystolithiasis following administration of caerulein was markedly lower than that of the normal subjects in the control group. The variations in the contraction of the gall bladder in time lapse following administration of caerulein to the patients with cholecystolithiasis strongly denied the possibility of either insufficient release of CCK or accelerated dissimilation of CCK in those patients. Based on the above findings, it was concluded that the sensitivity of the gall bladder to CCK decreases in the patients with cholecystolithiasis and that, in order to replenish it, the feed-back mechanism reacts to sufficiently promote the production of CCK in the duodenal mucosa. The similar mechanism was noted in the variations of the findings of normal subjects as age advanced.