Figure 4

Aβ- and nicotine-induced activation of ERK is decreased by the α7nAChR inhibitor MLA. Hippocampal slice cultures were pretreated for 30 min with media in the presence or absence of MLA (10 nM) followed by incubation with Aβ (100 nM, 5 min). A) Western blots. Phospho-ERK immunoreactivity was normalized to total ERK and expressed as percent of control. Data represent the mean ± SEM. n = 3-6; *p < 0.01. B) Immunocytochemistry. Confocal images were obtained from slices that were double labeled using antibodies specific for phospho-ERK (red) and the neuronal marker NeuN (green). Dual labeling is indicated by yellow/orange. Hippocampal slice cultures were pretreated for 30 min with media in the presence or absence of MLA (10 nM) followed by incubation with nicotine (500 nM, 5 min). C) Western blots. Phospho-ERK immunoreactivity was normalized to total ERK and expressed as percent of control. Data represent the mean ± SEM. n = 3-6, **p < 0.001. D) Immunocytochemistry. Confocal images were obtained from slices that were double labeled using antibodies specific for phospho-ERK (red) and the neuronal marker NeuN (green). Dual labeling is indicated by yellow/orange. Images were taken with a 20× objective and the scale bar represents 50 μm.