EFFECT OF ROUTE OF NUTRITION ON RECOVERY OF HEPATIC ORGANIC ANION CLEARANCE AFTER FASTING

Background. Previous work documented a 40% depression of hepatic indoc yanine green (ICG) clearance (Cl-ICG) in pigs fasted to 20% weight los s, with return to normal within 12 days of food refeeding. Cl-ICG in p igs is insensitive to changes in hepatic blood flow but very sensitive to changes in hepatic function (HF). Serial Cl-ICG determinations wer e performed to quantify the effect of route of nutrient delivery on re covery of HF. Methods. Fourteen pigs were fasted to 20% weight loss (1 2.8 days average) with both gastrostomy and intravenous catheters plac ed in each animal midway through the fast. Cl-ICG was measured before fast, after fast, and after 12 days refeeding through the enteral or p arenteral route at 125 kcal/kg/day with isonitrogenous, isocaloric die ts containing 9% fat. Urine and stool were analyzed for total nitrogen . Results. No significant differences appeared between groups in nitro gen output during fasting (4.5 +/- 1.2 gm/kg enteral, 4.6 +/- 1.2 gm/k g parenteral), in nitrogen intake (800 +/- 19 mg/kg/day enteral, 810 /- 10 mg/kg/day parenteral), or in before or after fast Cl-ICG, but en teral feeding produced more positive nitrogen balance. Cl-ICG improved significantly with enteral but not with parenteral feeding. Conclusio ns. Enteral feeding produces faster nitrogen accrual and reverses the depression of major pathways of bilirubin and organic anion excretion associated with malnutrition. Parenteral feeding failed to improve org anic anion clearance despite weight gain.