Fig. 1

Influence of osmolality of orally administered solutions on remaining fraction of water and luminal concentration of FD-4 in rats. A The remaining fraction of water and (B) luminal concentration of FD-4 in jejunum, ileum and colon after administration of FD-4 (10 μM) in purified water and hyperosmotic solution (10% NaCl) were measured by means of an in situ closed loop method for 30 min at 37 °C. The statistical significance between the different conditions was evaluated using an unpaired Student t-test. *P < 0.05, **P < 0.01, significantly different from purified water. Data are shown as means ± SEM (n = 6–9)