Figure 4. Retrograde amnesia: comparing Barnes maze performance before and after SE.

The difference in error and latency measures made between Day 1 of Week 5 and Day 4 of Week 1 were calculated and plotted for each of the four groups. The data were analyzed by two-way ANOVA with post-hoc Bonferroni tests. The difference in number of errors was significantly higher for both WT and nCOX-2 cKO mice that received pilocarpine compared to their respective saline groups (A,C). However, the difference in time it took to make initial contact with the hole (Primary Latency) was significantly higher only for the WT Pilocarpine group when compared to their respective saline group and to the nCOX-2 cKO Pilocarpine group (B). The WT Pilocarpine group also had a significantly higher difference in latency to enter the hole compared to the WT Saline but no other significant differences between groups were detected using this measure of memory (D). Main effect of treatment p<0.0001 in both panels A and C, p=0.022 in panel B, and p=0.001 in panel D; main effect of genotype p=0.244 in panel A, p=0.011 in panel B, p=0.620 in panel C and p=0.035 in panel D. The interaction between treatment and genotype was non-significant for every measure except primary latency (panel A, F=0.830, p=0.369; B, F=7.105, p=0.012; C, F=0.042, p=0.840; D, F=0.940, p=0.340). WT Saline n=8, nCOX-2 cKO Saline n=9, WT Pilocarpine n=7, and nCOX-2 cKO Pilocarpine n=11.