Table 3.
Passive and active membrane properties of juvenile and adult PV interneurons expressing, not expressing, or exogenously expressing SAP97
| Juvenile | Adult | ||||
|---|---|---|---|---|---|
| SAP97+ | SAP97- | SAP97+ | SAP97- | SAP97egfp | |
| Firing pattern | |||||
| Delay first AP (ms) | 440 ± 80 | 500 ± 80 | 510 ± 170 | 360 ± 90 | 276 ± 125 |
| ISI average (ms) | 28.9 ± 1.2 | 29.5 ± 1.5 | 26.9 ± 2.6 | 27.1 ± 2.2 | 26.1 ± 3.0 |
| Frequency adaptation | 0.96 ± 0.20 | 1.12 ± 0.12 | 1.42 ± 0.23 | 1.27 ± 0.11 | 0.72 ± 0.24 |
| Max ISI (ms) | 144 ± 35* | 62 ± 10 | 308 ± 118* | 53 ± 9 | 208 ± 46** |
| Min ISI (ms) | 18.2 ± 1.5* | 23.0 ± 1.7 | 15.5 ± 1.1* | 19.4 ± 1.7 | 12.3 ± 1.3** |
| Max/Min ISI | 9.2 ± 2.6* | 2.8 ± 0.5 | 20.2 ± 7.4* | 3.1 ± 0.8 | 17.4 ± 3.6** |
| CV frequency | 0.22 ± 0.04 | 0.17 ± 0.03 | 0.24 ± 0.03 | 0.20 ± 0.04 | 0.28 ± 0.02* |
| F/I slope (Hz/pA) | 1.8 ± 0.3* | 2.6 ± 0.4 | 0.9 ± 0.05*$ | 1.2$ ± 0.15 | 1.01 ± 0.11 |
| Passive | |||||
| Vm (mV) | -85 ± 1.8* | -90 ± 1.7 | -85 ± 1.7 | -88 ± 1.5 | -86 ± 2.0 |
| Rm (MΩ) | 88 ± 9.7** | 130 ± 13 | 118 ± 13**$ | 173 ± 14$ | 110 ± 15** |
| Rheobase (pA) | 450 ± 66* | 290 ± 40 | 270 ± 10*$ | 215 ± 20 | 346 ± 62* |
| AP shape | |||||
| AP threshold (mV) | -45.6 ± 2.5 | -47.3 ± 1.2 | -49.3 ± 1.6 | -49.7 ± 1.5 | -53.4 ± 2.1 |
| AP 10-90% rise (ms) | 0.25 ± 0.01 | 0.29 ± 0.01 | 0.21 ± 0.01* | 0.26 ± 0.02 | 0.20 ± 0.01** |
| AP half-width (ms) | 0.48 ± 0.02* | 0.63 ± 0.08 | 0.37 ± 0.02*$ | 0.46 ± 0.04$ | 0.32 ± 0.01*** |
| AHP peak (mV) | -25.3 ± 0.6 | -23.9 ± 1.0 | -24.5 ± 1.5 | -23.6 ± 1.0 | -23.6 ± 1.5 |
| AHP latency (ms) | 1.7 ± 0.1 | 3.0 ± 0.9 | 1.1 ± 0.1*$ | 1.5 ± 0.2 | 0.8 ± 0.04** |
| AHP area (V/s) | -210 ± 20** | -420 ± 70 | -140 ± 10***$ | -239 ± 15$ | -137 ± 10*** |
| Number of interneurons | 8 | 6 | 5 | 15 | 8 |
-
↵Juvenile (P15-P17) or adult (P56-P65) PV interneurons are characterized by firing pattern, passive membrane properties, and AP shape (see Materials and Methods). Values shown as mean ± SEM. A t test was used to determine whether the value for SAP97+ or SAP97egfp were significantly different from that for SAP97- within the same age (*p < 0.05, **p < 0.01, and ***p < 0.001) or between different ages within SAP97- or SAP97+ ($p < 0.05).