Figure 5. The giant slow inward currents can be reversed in direction at positive holding potentials.

A the giant slow inward current induced by MeHg (20 μM, at 45 min of exposure) in a Purkinje cell at a holding potential of −60 mV became an outward current at +60 mV. B, a family of mIPSCs were recorded from another Purkinje cell at a set of holding potentials of −80 to +60 mV after exposure to 20 μM MeHg for 50 min. Note that the giant slow inward current superimposed upon the mIPSCs recorded at −40 mV became outward current at +60 mV(again with mIPSCs superimposed upon it).