Figure 2

Effect of daily treatment with Aβ _1-40 on K⁺ and Ca²⁺ fluxes. After 6DIV, cortical neurons were treated daily with 1 μM Aβ_1-40 for up to eight days. Net ion fluxes were recorded daily from monolayers of cells grown on glass cover slips treated with poly-L-lysine for cell adherence. Data was acquired non-invasively using the microelectrode MIFE technique. Steady-state fluxes of K⁺ (A) and Ca²⁺ (B) are shown for one, three, six, and eight day treatment with Aβ_1-40. The sign convention is 'influx positive'. While K⁺ flux remained similar in control and cells treated with Aβ for one and three days, an increase in duration of the treatment to six days or longer led to a four-fold increase in K⁺ efflux from the neural cells (**P < 0.02). No difference in the levels of Ca²⁺ fluxes between control and Aβ treated cells was observed. Error bars are SEM (n = 4-7).