Table 1.

Cells recorded without cAMP in the pipette

Apamin-sensitive current,IaAHPApamin-insensitive current,IsAHP
Amplitude (pA)1-aCurrent density (A/F)1-aDecay time constant (msec)1-a,1-bnAmplitude (pA)1-aCurrent density (A/F)1-an
CA182.1  ± 16.90.45  ± 0.08225.6  ± 37.6647.1  ± 14.10.29  ± 0.086
CA3172.2  ± 21.90.69  ± 0.08365.3  ± 36.3940.8  ± 10.50.16  ± 0.049
DG8.2  ± 2.20.09  ± 0.021-c634.8  ± 9.90.41  ± 0.116
  • F1-a Values are mean ± SEM.

  • F1-b Fitting with double exponentials was used to give the best fit. The second exponential (not included in the table) had a slow time constant (0.5–5.5 sec) resemblingIsAHP and a very small, negative amplitude (−3.3 ± 0.4 pA), suggesting that it reflected a slight indirect enhancement of IsAHP caused by apamin-induced enhanced space clamp resulting in increased Ca2+ influx.

  • F1-c The amplitude of the current in DG cells was too small to reliably determine the decay time constant.