Resolution:
## Figure 2.
No developmental change in multiplicity at glutamatergic synapses onto interneurons
in stratum radiatum. (A_{1}) A typical recording at -80 mV from an interneuron in stratum radiatum from a P17
rat, upper trace shows AMPA sEPSCs under control conditions and lower trace shows
mEPSCs after wash-in of TTX. (A_{2}) At ages P7 - P18, TTX does not change the AMPA EPSC amplitude (an average reduction
of 1.2 ± 0.8 pA, P = 0.2, n = 4, two-tailed paired t-test). (A_{3}) TTX reduces AMPA EPSC frequency by 4.3 ± 1.1 Hz (P = 0.01, n = 4, one-tailed paired
t-test). (B_{1}) A typical recording at -80 mV from an interneuron in stratum radiatum from a P50
rat, upper trace shows AMPA sEPSCs under control conditions and lower trace shows
mEPSCs after wash-in of TTX. (B_{2}) At ages P30 - P50, TTX does not affect the AMPA EPSC amplitude (an average reduction
by 0.3 ± 0.9 pA, P = 0.8, n = 6, two-tailed paired t-test). (B_{3}) TTX reduces AMPA EPSC frequency by 2.4 ± 0.5 Hz (P = 0.003, n = 6, one-tailed paired
t-test). (C) The average multiplicity was 1.1 ± 0.1 (P = 0.09, n = 4, one-tailed one-sample
t-test with test value = 1) for the young age group (P7-18, open circles) and 1.1
± 0.1 (P = 0.17, n = 6) for the older rats (> P30, filled circles). (D) PPR measurements
from 8 interneurons in stratum radiatum (red filled circles) and 7 pyramidal cells
(green filled circles). The average PPR (50 ms) for the interneurons in stratum radiatum
is 1.17 + 0.19/- 0.16 (geometric mean +/- SEM) and for the pyramidal cells 1.43 +
0.22/- 0.19 (P = 0.4, two-tailed Student's t-test). Black filled circles show mean
± SEM and green and red open and filled circles show individual experiments. Asterisks
denote the level of significance as follows: *: P < 0.05, **: P < 0.01.
Riebe and Hanse |