Time-dependent effects of TGFβ pathway inhibitors on TER in the <i>in vitro</i> model.

<p>In case of inhibitor application, cells were incubated with inhibitors alone for 3βs + inhibitors for 2 h, 4 h and 6 h. Values prior to any treatment were taken as baseline (100%). A: The inhibition of TGFβ-R1 kinase activity by Ly364947 (Ly36) compared to untreated and vehicle-treated cells. B-D: TGFβs-affected TER values in the presence and absence of Ly364947. Effects observed for TGFβs are significantly inhibited by TGFβ-R1 inhibition. E: The inhibition of Smad3 by SiS3 compared to untreated and vehicle-treated cells. F–H: TGFβs-affected TER values in the presence and absence of SiS3. Inhibition of Smad3 resulted in attenuation of TGFβ effects. Data points represent mean values obtained from n = 6, generated by three independent repetitions performed in duplicate. SEM is indicated, p-values ±0.05 (Mann-Whitney-test) were considered significant (_*), p±0.005 highly significant (_**).