Hippocampal slices from prion protein null mice: disrupted Ca(2+)-activated K+ currents.

The intrinsic properties of hippocampal CA1 pyramidal cells were examined in mice lacking prion protein (PrP-null). The resting potentials, time constants, amplitude of the medium afterhyperpolarization (AHP) and spike firing accommodation did not differ from the control group. The PrP-null group differed in having lower input resistances, a lack of the late AHP and of a charybdotoxin-sensitive summated AHP. We propose that CA(2+)-activated K+ currents, in particular IAHP, are disrupted in PrP-null mice.