Do We Still Need to Collect Stool? Evaluation of Visualized Fatty Acid Absorption: Experimental Studies Using Rats

Abstract

Background: Short-gut syndrome is likely to impair enteric fat utilization. This study was undertaken to develop a clinical test of lipid absorption without fecal collection. Methods: The absorption of enterally fed radioactive long-chain fatty acid, β-methyl-p-(¹²³I)-iodophenylpentadecanoic acid was investigated with continuous chyle collection in rats. The changes in excretion and time-dependent biodistribution of radioactivity of the enterally fed agent were assessed in normal control animals. Similarly, sequential urinary excretion and biodistribution were studied along with scintigraphy using sham-operated and short-gut animals. Results: Approximately 64% of the enterally fed radioactivity was recovered in the collected chyle (24 hours). A comparison of normal control, sham-operated, and short-gut animals showed significantly less urinary and greater fecal excretions of radioactivity in short-gut animals. With the use of sequential scintigraphy, the small intestine, whole-body soft tissues, and urinary bladder were well visualized in sham-operated animals, whereas the large intestine and feces were demonstrated earlier in short-gut animals. Conclusions: Our results suggest that enteral feeding of the agent might be feasible for determining lipid absorption from the the dynamic changes of radioactivity in visualized abdominal organs and in urine. (Journal of Parenteral and Enteral Nutrition 22:22-26, 1998)