Investigation of regional differences in water and electrolyte absorption across the human colon by in vivo perfusion method.

Colonic perfusion studies were performed to evaluate regional differences in water and electrolyte absorption across the human colon. In 19 healthy male volunteers, a 5-lumen tube with two balloons was inserted into the colon by the endoscopic retrograde bowel insertion (ERBI) method and a 25 cm segment of either the right or the left colon was perfused with an isotonic electrolyte solution simulating the fasting ileal content at a rate of 5 ml/min. Additionally into 5 subjects of the right colon and 5 subjects of the left colon, PSP solution was injected and mean transit time was calculated by the dilution method. Higher absorption rates of water, Na and Cl were observed in the right than in the left colon. Mean transit time was longer in the left than in the right colon. It was considered that the right colon had greater absorptive capacity than the left. The colonic perfusion study by the use of ERBI method made it possible to determine the absorption of water and electrolytes in the right and left colon directly in man, and would be useful to elucidate the pathophysiology of colonic diarrhea.