Fig. 4.

Nucleoside triphosphate diphosphohydrolase-1 and -2 (NTPDase1 and -2) differently affect the gut barrier. Paracellular permeability of the distal colon wall from healthy wild-type (WT), Entpd1^−/−, and Entpd2^−/− mice and 2 wk after the dextran sulfate sodium (DSS) treatment. A: schematic of Ussing chamber. B: average fluorescein-5-(and-6)-sulfonate (FS) background subtracted fluorescence (ΔF) measured in intensity units (i.u.). Note that DSS-treated Entpd2 null have a marked increase of fluorescein-5-(and-6)-sulfonate (FS) fluorescence. Permeability was determined by assessing the slope obtained during the last four measurements. C: slope of last 4 measurements (in B) as a measure of relative permeability. *P = 0.028; **P = 0.002; ***P < 0.001, two-way ANOVA and Tukey's post hoc test; n = 7 mice, healthy WT (4 males and 3 females), DSS-treated Entpd1^−/− (4 males and 3 females), healthy Entpd2^−/− [4 males and 3 females (37 i.u./min removed as an outlier)]; n = 8 mice, DSS-treated WT (4 males and 4 females), DSS-treated Entpd2^−/− (3 males and 5 females); n = 13 mice, healthy Entpd1^−/− (8 males and 5 females).