Dose-response curve for rod formation in organotypic hippocampal slices and reversibility of Aβd/t-induced rods. (A) The same concentrations of Aβd/t and synthetic oligomer used in Figure 2A were applied to organotypic hippocampal slices. After 48 h, slices were fixed and rods immunostained and quantified per field averaged across the entire slice. The curves obtained are very similar to those in dissociated neurons but the measured parameters are different (average rods per field measured here vs. percent neurons with rods in Figure 2A). (B) Rods formed in response to Aβd/t in hippocampal slices reached their maximum value by 24 h (see Figure 2B). To determine rod reversibility, some of the slices were washed free of the Aβd/t and allowed to incubate another 24 h, whereas others had the Aβd/t present continuously. Controls were treated with the NC medium for 48 h or were left untreated (no difference). As previously shown for the rods induced by synthetic Aβ oligomers , the Aβd/t-induced rods are also reversible.