Differential Induction of Long-Term Potentiation in the Horizontal versus Columnar Superficial Connections to Layer II Cells of the Entorhinal Cortex
Figure 6
Expression of LTP in the horizontal
pathway was associated with a slight change in paired-pulse facilitation (PPF) ratio.
(a) Normalized scaled amplitude of
the peak EPSCs evoked by the first of a pair of test pulses separated by 60 milliseconds
(filled circles) and the normalized paired pulse facilitation ratio (open
circles) in a layer II cell is plotted against time. The inset shows two traces
reflecting averaged paired EPSCs at baseline (pre-HFS) and at 30 minutes post-HFS.
PPF ratio was calculated as the amplitude of the peak of the second EPSC
divided by the first. (b) Average
normalized scaled amplitude of PPF ratio in 10 cells. HFS at time zero induced
a short-term decrease which decayed back to near baseline levels. The values at
30 and 50 minutes after HFS, however, ( and , resp.) were significantly different
from baseline ().
