Translocation of particulates across the gut wall--a quantitative approach.

The translocation of latex particles across the epithelium of the rat small intestine and their transfer to internal organs was determined and quantified. The rate of particle uptake was also established. Particle uptake from the gut lumen to internal tissues was rapid as they were detected in all tissues examined within 30 minutes of oral administration. The maximum number of particles per gram tissue was detected in tissues of the small intestine. Particle number in spleen, kidney, lung, liver and brain increased with time, and in mesenteric lymph node, and heart tissues they decreased with time. Particles were also detected in bone marrow samples. These findings suggest that this animal model is useful in the evaluation and quantification of particle uptake and the determination of the tissues to where they are transported.