[In-vitro motility studies on the strips of the canine gallbladder (author's transl)].

In-vitro motility of the gallbladder was studied in the longitudinally cut full-thickness strips obtained from 61 mongrel dogs. The strips, 5 mm in width and 15 mm in length, were prepared from the fundus, body and infundibulum of the gallbladder wall and the motility was examined by the changes of contractile dynamics which were transduced on a pen chart recorder. The results were summarized as follows: 1. The specimen from three parts of the gallbladder exhibited spontaneous motility which was comprised of tonic and rhythmic contractions and they seemed to be stable approximately during the period from three and half an hour to six hours in the Tyrode solution. 2. There was a characteristic pattern which was specific for each three parts in the waves of spontaneous rhythmic contraction. The specimen from infundibulum showed almost regular waves which were predominantly comprised of greater amplitude than those of other two parts. 3. The effects of gastrointestinal hormones and similar substance, caerulein, tetragastrin and secretin were investigated on the activity. Caerulein and tetragastrin were found to be potent stimulant of the dog gallbladder. The stimulated contraction waves were uniform and the pattern could be described with using a certain mathematical expression.