Figure 5. 1-EBIO potentiates residual CFTR-mediated Cl⁻ secretion in CF rectal biopsies.

(A–F) Summary of effects of bumetanide (100 µM, basolateral) (A,B), CFTR_inh-172 (20 µM, basolateral) (C,D) and 1-EBIO (500 µM, basolateral) (E,F) on cAMP-mediated (IBMX/forskolin) and cholinergic (CCH) activation of equivalent short circuit current (I_sc') in rectal biopsies from control subjects, CF patients with no detectable Cl⁻ secretion (CF_absent) and CF patients with residual Cl⁻ secretion (CF_residual). All experiments were performed in the presence of amiloride and indomethacin. Only lumen-negative peak responses or plateau responses are shown for cholinergic (CCH) activation. Data are presented as mean±SEM. n = 4–26 individuals per group. *P<0.001, ^† P<0.01 and ^¶ P<0.05.