Effects of Pectin and Cellulose on Fat Absorption After Massive Small-Bowel Resection in Weanling Rats

The effects of pectin and cellulose on fat absorption after massive small-bowel resection were studied in rats. Weanling Wistar rats underwent 80% resection of the small intestine with gastrostomy, and fat emulsion labeled with ¹⁴C-linoleate was given via a gastrostomy tube for the fat absorption test on the 10th postoperative day. They were classified into three groups by diet as follows: E group, a fiber-free, chemically defined diet (CDD); EP group, CDD with 2% pectin; and EC group, CDD with 2% cellulose. The cumulative and hourly output of ¹⁴C in the expired air, the absorption rate of ¹⁴C in the intestine, and the metabolic utilization rate of ¹⁴C were calculated. The cumulative ¹⁴CO₂ output was significantly lower in the EC group than in the E and EP groups. However, there was no significant difference in the ¹⁴CO₂ output between the E and EP groups. The highest hourly ¹⁴CO₂ output in the E and EP groups was observed during the first 2 hours. However, in the EC group, this fluctuated at low levels. No significant difference in the 1-¹⁴C-linoleate absorption rate was observed between the E and EP groups, whereas it was significantly lower in the EC group than in the E and EP groups. The metabolic utilization rate of 1-¹⁴C-linoleate showed no significant difference among the three groups. These data suggest that an addition of pectin to CDD does not impair small intestinal absorption of 1-¹⁴C-linoleate after massive small-bowel resection, and an addition of cellulose decreases absorption of 1-¹⁴C-linoleate. (Journal of Parenteral and Enteral Nutrition 16: 255-258, 1992)