Figure 4.

Increased numbers of new senile plaques (SPs) in the cortex of APP/PS1 mice with and without murine p75^NTR saporin (mu p75-SAP) lesions were detected using in vivo multiphoton microscopy. Medians, maximums and minimums are shown and statistical differences were detected between both groups using Mann-Whitney U test for independent samples. (A) Numbers of plaques appearing per mm³ in ~3-month-old APPswe/PS1dE9 mice 7 and 14 days after the lesions (7 days: ** p = 0.006 vs. Sham; 14 days: ** p < 0.01 vs. Sham). When animals were compared between the day of the lesion and 120 days later there was an increase in SPs in lesioned animals, although differences did not reach statistical significance (p = 0.190 vs. Sham mice). (B) The same profile was observed in ~7-month-old mice (7 days: ** p < 0.01 vs. Sham; 14 days: * p = 0.044 vs. Sham). (D–K) Examples of SP deposition in an APPswe/PS1dE9 mouse 7 days after mu p75-SAP lesion (D, day 0; E, day 7) vs. a Sham mouse (F, day 0; G, day 7). Higher deposition was observed in lesioned APPswe/PS1dE9 mice 120 days after surgery (H, day 0; I, day 120), vs. a Sham mouse (J, day 0; K, day 120). The same fields were located using Texas Red dextran 70K (blue) for the angiograms and amyloid deposits were stained with methoxy-XO4 (red). White arrows indicate new amyloid deposits. Scale bar = 85 µm.