Postsynaptic Signals Mediating Induction of Long-Term Synaptic Depression in the Entorhinal Cortex
Figure 4
The induction of LTD was blocked in
a dose-dependent manner by including okadaic acid in the recording electrode
solution to block activation of protein phosphatase 1 (PP1). (a)
and (b) A low concentration of 0.1M okadaic acid failed to block LTD
induction, but raising the concentration to 1.0M resulted in a block of LTD
induction (compare traces in A1 versus A2). Responses in
control cells filled with 1.0M okadaic acid that did not receive conditioning
stimulation remained stable. The block of LTD by okadaic acid suggests that activation
of PP1 mediates LTD in the entorhinal cortex.