Disaccharide Feedings Enhance Rat Jejunal Macromolecular Absorption

Abstract

Summaryperiods of feeding at lower disaccharide concentrations, which do not induce symp~oms of intolerance. After the high lactose conDisaccharide feedings to post-weaning rats alters their jejunal centration feedings, there was evidence of morphologic damage to barrier to macromolecular absorption. Penetration of horseradish the epithelium of the jejunal mucosa. ~h~ disaccharide-induced peroxidase (HRP) across the jejunum was enhanced after short-increase in HRp absorption may be mediated by transport from term high concentration gavage (30 g*kg-'*da~-l) Of lactose that endocytotic vesicles across the epithelium (10, 12, 43).produces weight loss, osmotic diarrhea, and jejunal mucosal damage. HRP absorption was also increased by-longer term feedings of lower levels of disaccharide that did not produce body weight MATERIALS AND METHODS alterations, diarrhea, or cell damage. Rats without diarihea and gavaged with 7.5 g-kg-' .day-' of either lactose or maltose showed Animals and diet. Postweaning male rats (~r l : (WI) BR, char1e.s an increase in lumen to blood HRP absorption after 21 days of River Breeding Labs, WilmingtOn* MA) weighing g were feedings. Also, lactose or maltose in the solid food diet at 30 g.used. At this stage of development the rats have low lactase levels kg-'.day.' for 21 days did not lead to diarrhea but produced an (36). rats were fed a powdered Purina Rodent Chow (#5001, increase in jejunal lumen to blood HRP absorption. Rats having Ralston Purina Co., St. Louis, MO) and water ad libitum throughno diarrhea and receiving l5 g.kg-~ of lactose or maltose in out the study. The Purina chow diet contained 50% unrefined the drinking water for 21 days, showed an increase in jejunal HRP complex carbohydrate, 23.0% protein. 6.5% fats, and 6.8% minabsorption. When rats were fed either lactose or maltose for 21 erals. The balance corresponded to fiber, vitamins, and moisture. days glucose absorption became dependent upon the sugar In addition to this diet, disaccharides were experimentally adminconcentration in the perfusion medium. The kinetics of this glucose istered the rats. absorption are compatible with a decrease the 66unstirredv layer.

Intestinal barrier: An interface between health and disease

“…The effect was comparable to total parenteral nutrition 47 . In addition, feeding of disaccharides, especially lactose, increased jejunal permeability to macromolecules in rats 48 . In contrast, Sanderson et al .…”

Zinc treatment ameliorates diarrhea and intestinal inflammation in undernourished rats

“…In earlier studies, oral lactose (30 g/kg) produced weight loss and osmotic diarrhea to rats, with intestinal barrier leakage, observed by increased jejunal permeability to horseradish peroxidase (HRP) [22]. …”

“…In order to evaluate the effect of zinc supplementation on acute diarrhea, lactose-driven osmotic diarrhea was induced to the study rats, as described by Teichberg et al [22]. A subset of undernourished rats that received RBD was also challenged by a saturated lactose solution (monohydratated sodium lactose, Vetec Química, Rio de Janeiro, Brazil), which was given by gavage diluted in 2 mL of PBS, 30 g/Kg, starting on day 8 until day 14 to induce osmotic diarrhea.…”

Effect of Chronic Ethanol Administration and Dietary Protein Regimens on Intestinal Absorption of Macromolecules in Rats

“…Rothman et al [6] have also reported twice the amount of transported BSA in malnourished animals as compared with controls. Enhanced intestinal uptake of macro molecules in protein-deficient animals is prob ably due to increase in pinocytotic activity with deterioration of apical junctions and movement of protein molecules directly be tween the cells [6], Feeding of disaccharides to animals has been shown to increase HRP pen etration across the jejunum in postweaned rats [14], Since LP diet contained high sucrose con tent, it may be an additional factor for the observed increase in protein uptake under these conditions. Further, the effects of etha nol feeding to malnourished rats were opposite to those seen in normal protein (18%) fed rats.…”