Figure 2: Cotinine is neuroprotective by blocking the aggregation of Aβ. 7 DIV embryonic rat cortical cells were exposed to different forms of Aβ1-42 in absence or presence of cotinine 10μM for 24 h at 37°C. A) MTT analyses of cell viability of cells treated with pre-aggregated Aβ1-42 in absence or presence of 10 μM cotinine. B) MTT analysis of the cell viability of cortical cells treated with Aβ1-42 freshly dissolved in the culture media. Plots represent cell viability as percentage of vehicle-treated controls. C) Diagram representing the experimental design used. D) 100 μM Aβ1-42 was aggregated under conditions that favor oligomerization in the presence or absence of cotinine (100, 200, 500 μM). After 2 and 6 days of incubation at RT, aliquots of the oligomerization mix were analyzed by dot-blot immunoassays using the 6E10 and the highly specific anti- oligomeric Aβ antibody A11, (B). The differences were considered significant with p < 0.05 (*), and highly significant p < 0.001 (***), ns (not significant).