The pump function of cell lines.

<p>Short-circuit currents representing Na⁺/K+-ATPase activity from corneal cell monolayers on the insert well area of 4.67 cm² were calculated before and after addition of the Na⁺/K+-ATPase inhibitor ouabain. (A) Representative tracings of short-circuit current (<i>µ</i>A/well) obtained with cell monolayers of THCEC (Cyclin) (upper panel), HCEC (middle panel) and THCEC (E6/E7) (lower panel). THCEC (Cyclin) possessed equal transport activity to HCEC, whereas no pump function was detected in THCEC (E6/E7). (B) Time-course changes in the average short circuit current of cultured monolayers of cell lines at 1, 5, 10 and 20 min. Data shown are for (▴) THCEC (Cyclin) at PD8, (♦) THCEC (Cyclin) at PD 21, (•) HCEC and (▪) THCEC (E6/E7); all data are expressed as mean±SD of four replicate experiments of each cell line.