Transfer of lead through the rat's intestinal wall

The transfer of 203Pb through the wall of the duodenum, jejunum and ileum in 6- and 26-week old female albino rats was studied by the in vitro method of "everted sacs". The lead transport through, and the lead uptake in the wall was practically the same in all intestinal segments. The influence of age on these parameters of lead metabolism was not observed by the method we used. It seems that active transport of lead in all segments of the small intestine in 6-week old rats is negligible.