Table 1.
Effect of TBS and CS on synaptic efficacy and intrinsic excitability
| Bicuculline 10 μm | Bicuculline free | ||||
|---|---|---|---|---|---|
| TBS | CS | TBS | CS | ||
| EPSC amplitude | (% change) | 32 ± 13 (10)1-a | 25 ± 15 (5)1-b | ||
| EPSP amplitude | (% change) | 84 ± 16 (5) | 75 ± 19 (4) | −2.3 ± 4.5 (6) | −7.2 ± 9.6 (5) |
| Rin | (% change) | 37 ± 33 (10) | 41 ± 23 (5) | −0.06 ± 0.5 (6) | −10 ± 14.3 (5) |
| Th1 | (mV) | −7.9 ± 3.5 (10) | −9.1 ± 3.8 (5) | 1.8 ± 1.9 (6) | 1.6 ± 2.4 (5) |
Changes in synaptic efficacy and intrinsic excitability induced by TBS or CS in the presence of 10 μm bicuculline or in bicuculline-free extracellular solution (Rin was input resistance measured at potentials higher than −80 mV, andTh1 was spike threshold measured as explained in Materials and Methods). The number of cells is indicated in parentheses. In voltage-clamp experiments, EPSCs were recorded at −70 mV, the AMPA current was measured at the EPSC peak, and induction was performed by pairing TBS or CS with depolarization to −40 mV. In current-clamp recordings, induction was performed by TBS or CS from −70 mV, and control EPSPs were measured between 12 and 21 mV from the holding potential of −80 mV. There was no statistically significant difference at the 0.05 probability level between data obtained with TBS or CS.
From D'Angelo et al. (1999).
Obtained as in D'Angelo et al. (1999), except that CS was paired with 1 sec depolarization at −40 mV.