Figure 1.

HSP90 inhibition reduces T2R-stimulated intracellular NO production in H441 cells grown at the air–liquid interface (ALI). (A): Representative image of DAF-FM-loaded H441 ALIs stimulated for 10 min with 1 mM sodium benzoate (NaBenz.) or denatonium benzoate (denat benz.); fluorescence increased with denatonium benzoate but not sodium benzoate. (B): Average trace and bar graph (mean ± SEM) of four experiments as in (A). Significance determined by Student’s t-test; ** p < 0.01. (C): Average trace and bar graph (mean ± SEM of three experiments) showing response in cultures pre-loaded with BAPTA-AM and stimulated in the absence of extracellular Ca²⁺ (0-Ca²⁺_o) vs. control cultures pre-incubated with 0.1% DMSO only and stimulated in the presence of extracellular Ca²⁺. (D): Denatonium-induced DAF-FM fluorescence increases in H441 ALIs were inhibited by pretreatment with geldanamycin or L-NAME but not HSP70 inhibitor VER-15508. Average trace and bar graph of results from four independent experiments are shown. Significance determined by one-way ANOVA with Dunnett’s post-test comparing all values to control (denatonium only); ** p < 0.01.