RT-PCR analysis of α, β, γ, and δ epithelial Na channel (ENaC) mRNA expression in human pleural mesothelial cells and mouse pleural tissues. The expression pattern of ENaC subunits was confirmed with three independent experiments using the OneStep RT-PCR kit. The lanes from left to right represent α, β, δ, and γ ENaC subunits (α, β, δ, γ) and negative control (N). Arrows indicate a 500-bp marker. (A) M9K cells. (B) Mouse parietal pleural tissue. (C) Primary human mesothelial cells from healthy donor.