Figure 6. Inhibition of hilar GABAergic interneuron activity impaired spatial memory retrieval but not memory retention.
(A) Protocols of mice used and laser illumination during hidden platform (H1–5) and probe (P-24 h, P-48 h, P-72 h) trials in the MWM test. (B) Learning curves of I12b-Cre mice injected with AAV1-DIO-eNpHR3.0-eYFP virus without laser illumination in the hidden platform trials (H-Off) of the MWM test. Points represent averages of daily trials. H, hidden platform sessions (two trials/session, two sessions/day); H0, first trial on H1. Y-axis indicates time to reach the target platform (escape latency). Values are mean ± SEM and statistically evaluated by repeated measures ANOVA. (C–E) Percent time spent in the target quadrant versus the other quadrants in the probe trial performed 24 (P-24 h), 48 (P-48 h), or 72 (P-72 h) hours after the last hidden platform trial with (On) or without (Off) laser illumination. Values are mean ± SEM. *p<0.05, **p<0.01 (two tailed and unpaired t-test). F–H, Platform crossings in the probe trial performed 24 (P-24 h), 48 (P-48 h), or 72 (P-72 h) hours after the last hidden platform trial with (On) or without (Off) laser illumination. Values are mean ± SEM. n = 8 mice/group. *p<0.05, #p = 0.05 (two tailed and unpaired t-test).