Figure 2.

Ussing chamber analysis: TEER and [³H]-mannitol flux after 4 h incubation with quercetin. (A) TEER of PPs after 4 h of incubation with different concentrations of quercetin as percentage of the initial resistance before quercetin addition. No effect of quercetin on TEER could be observed (n = 6–32). (B) [³H]-mannitol flux from apical to basolateral in PPs after 4 h was not influenced by quercetin (n = 13). (C) In the VE, 400 µM concentration led to a significantly higher TEER compared to the control (p = 0.006, n = 31–32). (D) [³H]-mannitol flux in the VE was not changed (n = 13). Values are given as mean ± SEM and asterisks indicate significant difference, ** = p ≤ 0.01.