TNF and Diarrhea: Diarrhea, liver insufficiency, renal (tubular) insufficiency, and accumulation of lung water (think multi-organ failure here) are clinical manifestations of the type of barrier leak that we observe in this study (e.g., the TNF-α-induced leak) as revealed by decreased TER (i.e., increased passive transepithelial leak (conductance) of salt and water) and increased 14C-D-mannitol permeability (indicative of leak of sugars, amino acids, and other small molecules).