[Experimental model of impaired gastrointestinal macromolecular permeability]

Gastrointestinal macromolecular permeability for polyethylene glycol (PEG)-4000 was studied in Wistar rats with resected distal portion of the small intestine, experimental colitis induced by chemical toxicant (acetic acid) and in rats receiving oral ethyl alcohol. Gastrointestinal permeability in animals with resection transiently increased during the first two weeks after operation and returned to normal thereafter. Colitis induction resulted in marked (2.5-fold) growth of permeability for PEG-4000 on day 7 and in a less significant increase on day 21. In animals exposed to ethyl alcohol no changes in macromolecular permeability were noted for PEG-4000 and food protein (chick's egg albumin). It is concluded that the model of colitis induced by chemical toxicants is most suitable among the models tested for experimental research on dietetic correction of altered macromolecular permeability.