Effect of retrograde electrical pacing on jejunal absorption of xylose and vitamin C.

Does retrograde electrical pacing of a continuously perfused jejunal segment increase absorption of xylose and vitamin C? Proximal jejunal segments (75 cm) were isolated from the intestinal stream in 5 dogs, and recording and stimulating electrodes attached. A solution containing 139.9 mmol/liter xylose, 0.57 mmol/liter vitamin C, and 79.9 mmol/liter sodium chloride was infused into the loop at a rate of 2.8 ml/min. Effluent from the loop was collected in 5-min aliquots during 3 consecutive periods of 30 min, and the composition of each analyzed. During the second period, when retrograde electrical pacing was performed, there was a significant decrease in water, xylose, and vitamin C output (p less than 0.0001).