EFFECTS OF NATIVE AND HYDROLYZED WHEY-PROTEIN ON INTESTINAL REPAIR OFSEVERELY STARVED RATS AT WEANING

The aim of this study was to evaluate the effect of two sources of die tary nitrogen (isolated whey protein and hydrolyzed whey protein) on t he intestinal repair of malnourished rats at weaning. The malnutrition was achieved by a 3 days' starvation period. Normally fed male Wistar rats were used as controls. Intestinal repair was studied after a ref eeding period of 4 days. The parameters studied included nitrogen bala nce, lactase, sucrase, isomaltase, and maltase activities of the jejun um; liver acetylcholinesterase and glutamate dehydrogenase activities; and the serum amino acid profile. In addition, tests of intestinal pe rmeability to macromolecules were performed by measurement of ovalbumi n and beta-lactoglobulin in serum. Both diets led to the recovery of t he severely starved rats, in terms of the values of all the parameters evaluated. The serum beta-lactoglobulin was the only exception, becau se its concentration was significantly lower in the normally fed anima ls. This study suggests that the intestinal mucosal barrier is not com pletely repaired, even after a 4-day refeeding period, to the point of being suitable to accept an increase in the uptake of antigens.