A cell-permeable pyrimido-pyrrolo-quinoxalinedione (PPQ) compound that targets the intracellular nucleotide binding domain(s) of CFTR and inhibits CFTR-mediated chloride current in a reversible and voltage-independent manner. Single channel recordings of CFTR-expressing FRT cells upon forskolin (Cat. No. 344270) and IBMX (Cat. No. 410957) stimulation indicate that the nature of PPQ-102 inhibition is due to a stabilization of the channels in a closed state (7.8- vs. 0.4-fold increase of mean channel close vs. open time, respectively, with 1 μM PPQ-102). PPQ-102 at 5 μM is shown to completely prevent Sp-8-Br-cAMP- (Cat. No. 116818) induced cysts formation and reduce the size of preformed cysts in an ex vivo murine neonatal kidney organ culture.
