American Journal of Clinical Nutrition, Vol 23, 1331-1338, Copyright © 1970 by The American Society for Clinical Nutrition, Inc.

Lipid Absorption and Lipid-Reesterifying Enzyme Activity in Small Bowel of the Protein-Deficient Rat

¹ From the Department of Medicine, Albany Medical College, Albany, New York 12208

Rats were made protein deficient by offering a protein-free diet for 4 weeks. The specific and total activities of fatty acid-CoA ligase and acyl-CoA-monoglyceride acyltransferase were determined on microsomal fractions of jejunal mucosa in fasting experimental and control animals. The activity of acyl-CoA-monoglyceride acyltransferase was also measured in non-fasting rats. In vivo studies of lipid absorption using both radioactive triglyceride and free fatty acid were also performed. Results of the in vivo studies from protein-deficient rats were compared with two sets of controls, one of the same age and one of the same size.

Specific activities of the enzymes were similar in experimental and control animals both in the fasting and nonfasting state. Total activities of these enzymes were significantly lower in experimental animals, but these differences were no longer apparent when total activities were expressed per gram wet weight of mucosa. In vivo studies of lipid absorption showed no gross evidence of malabsorption of either triglyceride or free fatty acid in protein-deficient rats.