Table 1.

Physiological properties of four groups of necortical neurons

PYR (n = 29)FS (n = 34)RSNP (n = 48)IS (n = 10)1-a
fmax(Hz)20  ± 5104  ± 2542  ± 14n.d.
PYR. < RSNP < FS
Early accommodation66.2  ± 7.1%15.3  ± 15.0%46.6  ± 13.6%n.d.
(finitialf200)/finitialFS < RSNP < PYR.
Late accommodation7.4  ± 4.7%6.0  ± 5.9%10.1  ± 8.2%n.d.
(f200ffinal)/finitialn.s.
t1/2 early (msec)15  ± 811  ± 829  ± 17n.d.
PYR, FS. < RSNP
First spike duration (msec)1.52  ± 0.290.59  ± 0.131.06  ± 0.280.95  ± 0.17
FS < RSNP, IS < PYR.
Second spike duration (msec)2.68  ± 0.670.61  ± 0.131.35  ± 0.851.17  ± 0.35
FS < RSNP, IS < PYR.
Spike duration increase75.6  ± 27.7%3.7  ± 5.9%21.4  ± 30.6%23  ± 25%
FS < RSNP, IS < PYR.
First spike amplitude (mV)92  ± 983  ± 888  ± 1088  ± 10
n.s.
Second spike amplitude (mV)61  ± 1478  ± 779  ± 1365  ± 13
PYR., IS < FS, RSNP
Spike amplitude reduction34.1  ± 10.9%6.4  ± 4.6%13.1  ± 11.1%26  ± 11%
FS < RSNP < PYR., IS
First AHP (mV)−1  ± 3−24  ± 4−15  ± 6−10  ± 5
FS < RSNP, IS < PYR.
Second AHP (mV)−7  ± 3−25  ± 4−15  ± 5−13  ± 4
FS < RSNP, IS < PYR.
Input resistance (MΩ)245  ± 93240  ± 106389  ± 138403  ± 122
PYR., FS < RSNP, IS
Resting potential (mV)−72  ± 4−73  ± 8−66  ± 7−70  ± 7
n.s.
  • Values given are mean ± SD. n, Number of cells; n.d., not determined; n.s., no statistically significant difference. FS, Fast spiking cells; IS, irregular spiking cells; RSNP, regular spiking nonpyramidal cells; PYR, pyramidal cells. <, Significantly smaller with p = 0.01. Statistically significant differences were determined using the Mann-Whitney U test. Physiological parameters were measured as described in Materials and Methods. finitial, Frequency at the beginning of the discharge; f200, frequency 200 msec after the beginning of the discharge; ffinal, frequency at the end of the current stimulation;fmax, instantaneous discharge frequency measured at 600 msec during high intensity current injection (>200 pA).t1/2 early, Time needed to reach 50% of the early accommodation.

  • F1-a  Accommodation parameters andfmax could not be calculated for IS cells because of their bursting behavior. The five IS cells analyzed for the expression of CR, VIP, ChAT, GAD65, and GAD67 were not included in this table because they were recorded at 34°C.