Figure 2.
The effect of subthreshold Aβ pretreatment on prolonging thrombin signaling. A, N9 microglial cells were pretreated with 500 nm Aβ1-42 (arrow 1) for 5 min, followed by treatment with 100 nm thrombin (arrow 2). Changes in [Ca2+]i were measured from three separate experiments, as described previously (Suo et al., 2002, 2003a). Mean values at each point were plotted. Error bars were omitted to make the figure more legible, but the SDs were all <46.7 nm. For B and C, N9 microglial cells were pretreated with Aβ1-42 (500 nm) for 5 min, followed by thrombin (Thr.; 100 nm) treatment for either 20 min or 24 hr as indicated. Western blots were performed as described in Materials and Methods with antibodies against phospho-specific and total p44/42 MAPKs (Pp44/42 and Tp44/42; B) and p38 MAPK (Pp38 and Tp38; C). Reprobe of the membranes with anti-γ-tubulin (γ-Tub) was used as an unrelated protein control. Cont., Control.