TOTAL PARENTERAL-NUTRITION INCREASES UPTAKE OF LATEX BEADS BY PEYERS-PATCHES

Background: Dysfunction of the intestinal barrier, as evidenced by inc reased intestinal permeability and bacterial translocation, has been r eported under total parenteral nutrition (TPN). However, the role of P eyer's patches on the intestinal barrier in TPN is not well understood . We investigated whether TPN alters the uptake of microparticles by t he follicle-associated epithelium of Peyer's patches. Methods: Twenty rats were divided into two groups, a control group and a TPN group. Fl uorescent polystyrene latex beads, 3.2 +/- 0.2 mu m in diameter, were used as a probe for measuring the uptake by Peyer's patches. After 1 w eek of consuming either the control or TPN diet, rats were killed. On the day of killing, 0.1 mL, of latex beads solution was injected into 1-cm length of ileal loop, within 10 cm of the ileocecal valve. Sample s were taken after 30 minutes of injection, sectioned by cryostat, and then viewed under a fluorescent microscope. Follicle-associated, epit helial length and particles were counted using a confocal laser scanni ng microscope. The number of particles within each compartment was sta ndardized per unit length of epithelium of Peyer's patches. Results: P article numbers within Peyer's patch dome of the TPN group were signif icantly increased compared with those of the control group (p <.01). C onclusions: These data suggest that dysfunction of the intestinal barr ier in TPN might be associated with a change of uptake by Peyer's patc hes.