Fig. 5.
PAR2 alterations in airway epithelial ion conductance are largely mediated by [Ca2+]i increases. Ussing chamber experiments were conducted under voltage-clamp conditions. A: representative Isc traces showing that apical addition of 2at-LIGRLO(PEG3-Pam)-NH2 (10 μM) alone evoked a robust PAR2 response that was attenuated with BAPTA (50 μM) preincubation. B: MTE cells pretreated with BAPTA showed a diminished loss of TER after the apical application of 2at-LIGRLO(PEG3-Pam)-NH2 (10 μM) compared with cells treated with 2at-LIGRLO(PEG3-Pam)-NH2 (10 μM) alone. C: quantification of Isc and TER demonstrating a significant reduction in the PAR2 response to 2at-LIGRLO(PEG3-Pam)-NH2 (10 μM) in MTE cells pretreated with BAPTA (50 μM) (BAPTA treatment: ΔIsc 2.54 ± 0.346 μA/cm2 and ΔTER −84.07 ± 3.44 Ω·cm2, n = 3; BAPTA free: ΔIsc 17.09 ± 1.88 μA/cm2 and ΔTER −270.3 ± 51.1 Ω·cm2, n = 6). *Significant difference (P < 0.05 by unpaired Student's t-test).