Aβ42 impairment of LTP is prevented by inhibition of p38 MAPK, but not JNK in entorhinal cortex slices from WT mice. A, LTP induction and maintenance was not affected by continuous perfusion with 1 μm SB203580 (p38 MAPK inhibitor) (filled square) or 20 μm SP600125 (JNK inhibitor) (gray diamonds). Top, Representative field potentials recorded before and 50 min after HFS slices treated with SB203580. B, SB203580 (1 μm), but not SP600125 (20 μm), perfusion prevented LTP blockade in Aβ42-treated slices (bath application at 200 nm corresponding to dark bar). Top, Representative field potentials recorded before and 50 min after HFS in slices treated with SB203580 and Aβ42. Calibration: A, B, 1 mV, 5 ms. C, Input–output curves. Slice perfusion with ACSF containing 1 μm SB203580 (filled squares) or 20 μm SP600125 (open triangles) did not change the input–output curves with respect to vehicle-treated slices (open circles). D, Paired-pulse facilitation, PP ratio was not modified in 1 μm SB203580- and 20 μm SP600125-treated slices with respect to vehicle-treated slices; other conventions are as in C. Error bars indicate SEM.