Effect of Sp-cAMPS on sEPSP. (A) Cumulative sEPSP
amplitude distributions show that cAMP-mediated LTP is associated with
significant increases in amplitudes of sEPSPs recorded both during the
early phase (40–60 min after Sp, shaded line) and during the late
phase (100–120 min after Sp, thin line), compared with the baseline
(thick line). (B) Frequency of sEPSPs was increased
during both early and late phases of LTP. *,
P < 0.05, compared with the baseline.
(C) No significant increase in the amplitude of sEPSPs
was observed when Rp-cAMPS (Rp, 100 μM) was coapplied with Sp-cAMPS
(50 μM). (D) Anisomycin (aniso, 20 μM) prevented the
Sp-cAMPS-associated increase in the amplitude of sEPSPs. Error bars
indicate ± SEM.