Figure 5.

Chronic mucosal Nys treatment promotes sustained Na⁺ hyperabsorption in airway epithelial cells in the absence of cell toxicity. (A–C) EVOM measurements of HBEs bioelectric properties in naïve, KBR-, and Nys-treated cultures. (A) transepithelial voltage (V_T); (B) transepithelial resistance (R_T); and (C) calculated equivalent current (I_eq). Data are shown as mean ± SEM, n = 6 individual donors, 2 to 4 cultures for each treatment, *P < 0.001 significantly different vs. naïve cultures. (D) Representative images illustrating the absence of ethidium homodimer-1 staining (marker of cell death) in naïve, KBR-, and Nys- treated cells subjected to the DEAD/LIVE cell fluorescence assay. Positive control = digitonin-treated HBEs. (E) Lactate dehydrogenase (LDH) activity in the basolateral media of naïve, KBR-, and Nys-treated cultures after 96 hours of Nys treatment. Data are shown as mean ± SEM, n = 3 individual donors, 2 cultures for each treatment. (F) Time-course of lactate accumulation in the serosal media of naïve, KBR-, and Nys-treated cultures. Data are shown as mean ± SEM, n = 4 individual donors, 2 cultures for each treatment; *P < 0.001 Nys versus naïve and KBR-treated cultures, ^•P < 0.001 KBR versus naïve cultures.