Regulation of the CFTR channel is accomplished through the activation of surface receptors that couple to adenyl cyclase, raise cAMP cellular levels and thus activate PKA. This has been demonstrated for the adenosine and ß2 adrenergic receptor and the vasopressin hormone among others.nBesides enhanced Cl- conductance, activation of CFTR also leads to the regulation of other ion channels. The best-studied case is its interaction with the epithelial Na+ channels (ENaC), although it can probably regulate other ion channels as well (Kir1.1 for example). The mechanism by which CFTR regulates other ion channels is not clear, but it may involve protein-protein interactions via molecules that interact with its C-terminal PDZ binding motif, such as the NHERF adaptor protein.