Rapid decrease in transepithelial electrical resistance of human intestinal Caco-2 cell monolayers by cytotoxic...

The transepithelial electrical resistance (TEER) of human intestinal Caco-2 cell monolayers cultured on a permeable filter rapidly decreased on apical exposure of the monolayer cells to such cytotoxic membrane perturbents as benzalkonium chloride and saponin. This decrease in TEER occurred at lower concentrations of these toxicants and at earlier stages of incubation than those for the release of intracellular lactate dehydrogenase, which is commonly used as a parameter for assessing cell membrane damage. The TEER decrease caused by the toxicants was associated with increased transepithelial permeability of the cell monolayer, as well as with subtle changes in the cytoskeletal structure, suggesting that membrane perturbation by the toxicants induced cytoskeletal changes that resulted in disruption of the tight junction and a subsequent increase in paracellular permeability. The rapid TEER change caused by the cytotoxic membrane perturbents suggests that TEER measurement would provide a simple and sensitive method for evaluating membrane-perturbing toxicants.