Fig. 11.

In vivo jejunal fluid movement and NHE3 activity in surface colonocytes in NHERF1/PDZK1 double-deficient mice. a Fluid absorption under basal conditions (black bars) and in the presence of FSK (gray bars) was determined in NHERF1/PDZK1^−/− jejunum. The reduced basal fluid absorption (p<0.05) and the reduced response to FSK was similar to what was observed in the NHERF1^−/− jejunum as shown in Fig. 1a (n=5). b In contrast, the reduction of the basal acid-activated NHE3 transport rate (black bars) in colon surface enterocytes was significantly larger (**p<0.05) in NHERF1/PDZK1 double-deficient mice than in NHERF1-deficient mice (see Fig. 5). Furthermore, inhibition by FSK was completely abrogated (n=6)