TNF and pseudohypoaldosteronism, type IB1, autosomal recessive: Since the α-subunit is supposed to play a prominent role in the ENaC current activation by TNF and TIP peptide, we investigated whether TNF and solnatide can also enhance αβγ-ENaC current in α-ENaC loss-of-function frameshift mutants, i.e., αI68fs, αT169fs, αP197fs, αE272fs, αF435fs, αR438fs, αY447fs, αR448fs, αS452fs, and αT482fs (Table 2), which have been reported to cause PHA1B.