Intestinal lipid absorption in the nephrotic rat.

Abstract

There is limited data on intestinal lipid absorption in the nephrotic syndrome. This study investigated whether the efficiency of intestinal lipid absorption is altered in nephrotic lymph-fistula rats. The nephrotic syndrome was induced in nine Sprague-Dawley rats by an i.v. injection of puromycin aminonucleoside in saline; seven control rats received saline only. At 10 to 14 days after injection, the main intestinal lymph duct was cannulated for collection of lymph. The duodenum was also cannulated and a fasting saline-glucose solution was infused overnight at 3 mL/h. The next day, the infusate was changed to a lipid emulsion that contained (14C) cholesterol and (3H)triglyceride (triolein) that was infused at 3 mL/h for 8 h. During the last hour of fasting and during the lipid infusion, lymph flow in the Nephrotic group averaged 0.6 mL/h higher than the Control group (P = 0.02). No significant differences were found between the two groups in recovery of infused radioactive cholesterol (P = 0.37) or triglyceride (P = 0.38) from the gastrointestinal lumen, small intestinal mucosa, or lymph. Lymphatic output of chemically measured cholesterol was also similar (P = 0.96). These results suggest that mucosal uptake and lymphatic output of cholesterol and triglyceride are not altered in the nephrotic syndrome.