Fig. 6

Delivery of sAPPα, either in vivo or in vitro, after plaque development, completely rescued the impaired LTP in Tg-controls. a Chronically administered sAPPα by lentivirus-mediated expression in adult (10 months) Tg mice completely rescued the deficit in hippocampal LTP, measured 3 months after viral transduction (at 13 months of age). LTP measured 60 min after TBS (arrow) revealed a significant deficit in LTP expression in Tg-control mice compared to WT-controls (WT-controls: 71.1 ± 6.7%, n = 11; Tg-controls 36.3 ± 10.0%, n = 9; p = 0.008). This deficit was completely rescued by sAPPα over-expression (Tg-sAPPα: 72.2 ± 2.4%, n = 12; p = 0.008 compared to Tg-controls). b LTP induced in hippocampal slices from aged Tg mice (18–20 months of age), was impaired compared to WT-controls when measured 60 min post-TBS (WT-control: 67.2 ± 7.5%, n = 9; Tg-control: 29.4 ± 4.7%, n = 7; p = 0.002). LTP expression was again completely rescued by acutely applied recombinant human sAPPα (10 nM) beginning 30 min before delivery of the TBS (Tg-sAPPα: 73.7 ± 16.7%, n = 10; p = 0.737 compared to WT-controls, p = 0.048 compared to Tg-controls). No effect of sAPPα on WT-control LTP was observed (WT-sAPPα: 62.1 ± 9.4%, n = 6; p = 0.684)