Localization of steady currents in the lens.

Steady currents around the rat lens were measured with a vibrating probe. Inward currents were found at the anterior pole and to a lesser degree at the posterior pole. Outward currents were localized at the equator. These currents were inhibited and even reversed by high concentrations of potassium. Ouabain blocked currents after 24 hrs but not after 6 hrs of exposure. The composition of the medium was not critical. For example, currents were observed in NaCl and in MgSO4 solutions.