ApoE isoforms alter NMDA receptor-dependent field potentials. A) Synaptic transmission in the presence of 20 μM CNQX (dashed line) and 100 nM human apoE (solid line). Expressed as slope of fEPSP, standardized to the first 20 minutes of recording. B) Average potentiation of last 20 minutes of recording. control = black circle, n = 8; rhapoE2 = blue square, n = 8; rhapoE3 = purple inverted triangle, n = 7; rhapoE4 = red triangle, n = 6. Data expressed as mean ± SEM. *p < 0.05, **p < 0.01, ANOVA with Bonferroni's posttest.