Whole-cell currents from noncultured human lens epithelium.

Perforated patch techniques were used to measure whole-cell ionic currents in freshly dissociated human lens epithelial cells that had not been subjected to culture media or serum. With a 150 mmol/l K+ internal solution, the cells had resting voltages of -27.4 +/- 4.7 mV (mean +/- standard deviation [SD]) and capacitances of 10.4 +/- 2.8 pF (mean +/- SD). The input resistance of the cells was 1.6 +/- 0.7 G omega (mean +/- SD) at large negative voltages. A delayed outwardly rectifying K+ current was found in most cells studied. Current magnitudes of 1-2 nA at +80 mV were common. The current had selectivities, activation time constants, deactivation time constants, open probability versus voltage relationships, and inactivations similar to those of the delayed rectifying K+ current found in many cell types and studied previously in cultured human lens epithelium. These results verify the existence, at high density, of these currents in noncultured human epithelial cells.