1. Multi-site recordings in Tg4510 mice
Liam Scott

2. 7 month male Tg4510 mice show decreased MWM performance and hippocampal cell loss
3 vs. 7 month old Tg4510 male mice show:
Area (mm2)
Hippocampus: Area
(Wildtype for comparison) 3m 7m
Data: Yabe, Moore, Roof
Data: Kawabe, Klein, Milici

3. Stimulation of the nPO drives the hippocampal EEG in anesthetized rats and mice
6-seconds
NPO
Hippo
EEG
Stimulus
5-HT
Hippocampal Formation
pcells
Median Raphe
Glu
gaba
ACh
Medial Septum
Nucleus Pontis Oralis
(nPO)
Supramammilary Bodies
(SUM)
Adapted from: RP Vertes (2005) Hippocampus 15:923-35
= +
= -
0.06
0.08
0.10
0.12
0.14
0.16
5.5
6.0
6.5
7.0
7.5
8.0
Frequency (Hz)
Stim Current (mA)
Theta Frequency
0.06
0.08
0.10
0.12
0.14
0.16
15.0k
20.0k
25.0k
30.0k
35.0k
40.0k
45.0k
50.0k
Theta Power
Theta Power (V2)
Stim Current (mA)

4. Determining electrode position using stimulation of nPO

5. 7 month male Tg4510 mice show decreased nPO-evoked hippocampal theta power and total power
Peak Frequency
Relative Theta Power
Theta Power
Total Power ** *
(*=P<0.05, **=P<0.01, ***=P<0.001 ; unpaired t-test)

6. Perforant path – dentate gyrus LTP

7. Determining electrode position using stimulation of perforant path

8. 7 month male Tg4510 mice show reduced amplitude of perforant path-evoked dentate gyrus population spike

9. 7 month male Tg4510 mice show reduced amplitude of perforant path-evoked dentate gyrus population spike

10. 7 month male Tg4510 mice show no change in perforant path - dentate gyrus LTP

11. control
CA-1 DG

12. Tg
CA-1
CA1 population spike DG
DG population spike

14. Summary
Stimulated theta
No change in theta frequency or relative theta
Reduction in theta power and total power
PP-DG LTP
Reduction in amplitude of evoked population spike
No change in LTP due to HFS
All observations can be explained by reduction in cell number in hippocampal formation???