Table 1.

Intrinsic electrophysiological properties of layer II principal cells in the medial entorhinal cortex

Control n 3-7 d Post-status n
Resting membrane potential (mV) -59.1 ± 0.9 18 -57.9 ± 0.6 20
Input resistance
   Peak (MΩ) 96 ± 12 14 85 ± 8 18
   Steady (MΩ) 78 ± 14 14 61 ± 9 18
Sag ratio (%) 66 ± 4 14 61 ± 3 18
Single action potential
   Threshold (mV) -46.1 ± 0.7 18 -45.5 ± 0.5 20
   Amplitude (mV) 102.5 ± 2.9 18 96.9 ± 2.6 20
   Half-duration (msec) 0.9 ± 0.0 18 0.9 ± 0.0 20
   fAHPa amplitude (mV) 1.7 ± 1.2 18 1.6 ± 0.9 20
   ADPb amplitude (mV) 6.3 ± 0.9 18 6.0 ± 0.6 20
   mAHPc amplitude (mV) -1.7 ± 0.2 18 -2.1 ± 0.2 20
   mAHP half-duration (msec) 54.8 ± 5.3 18 64.1 ± 3.2 20
Repetitive firing
   Slope (spikes/nA) 45 ± 4 9 40 ± 3 18

  • Values represent mean ± SEM. There were no significant differences in the values of control versus 3-7d post-status epilepticus rats (t test).

  • ↵ a Fast afterhyperpolarization

  • ↵ b afterdepolarization

  • ↵ c medium-duration after hyperpolarization