Study of small bowel transport pattern in fasted, conscious rats with an intact gastrointestinal tract. A methodological study with bile-excreted 99Tcm-Solco-HIDA

A method is presented for studies of small bowel propulsion in conscious rats with an intact gastrointestinal tract. A bile-excreted test substance, 99Tcm-Solco-HIDA, was infused intravenously for time periods varying between 0.25 and 5 h. Immediately after the infusion, radioactivity was recorded from the excised bowel specimen. The activity distribution along the small bowel was always found to be 'peaky', i.e. the intestinal contents were transported in portions separated by fairly long completely empty regions. In a control experiment with simultaneous intravenous infusion of 99Tc-Solco-HIDA and infusion of a nonabsorbable test substance (125I-PVP) through a permanent duodenal catheter a similar activity distribution was observed. This indicates that the peaky appearance of the activity distribution is not due to a periodicity in the discharge of bile but reflects small bowel propulsive activity.