Absorption of paraquat by rat gut in vitro. Regional differences

The absorption of radioactively labeled paraquat was measured in rat ileum, jejunum and colon by a micro everted sac technique (Semenza and Muhlhaupt, 1969). The absorption rate increased linearly over the range of concentrations measured (10(-5) to 10(-2) M) and was enhanced by nearly 50% in the absence of sodium ions. The absorption rate decreased in the order: ileum, jejunum, colon whereby in the colon still 65% of the values of the small intestine were observed.