Figure 3.

LTP induction within a narrow critical period enhances cell survival in the DG. (A) Top: Experimental schedule. Bottom: Number of BrdU-labeled cells at various time points after BrdU injection. BrdU was given twice a day for 4 consecutive days, and cells were counted in the sampling areas 1, 7, 14, 21, and 28 days after the last injection of BrdU. (B) Top: Experimental schedule for the effect of HFS (500) on cell survival. Bottom: Right/left (R/L) ratio of the number of BrdU-NeuN double-labeled cells at the indicated times after HFS treatment. (C) Immunoreactivity for BrdU (red) and NeuN (green) 28 days after the last BrdU injection in the DG of a rat treated with HFS (500) 7 days after the last BrdU injection. Scale bars, 50 μm. (D) Experimental schedule for the effect of CPP on the enhancement of survival by HFS. (E) Top: Typical fEPSP traces evoked 1 days before HFS (left), 1 days after HFS (middle), and 7 days after HFS (right). Bottom: PS amplitudes of the DG before HFS (Pre) and 1 day and 7 days after HFS (500) in the CPP-alone and CPP-HFS groups. (F) R/L ratio of the number of BrdU-NeuN double-labeled cells in the CPP-alone and CPP-HFS groups. * P < 0.05, * * P < 0.01, N.S indicates 'Not Significant'. Error bars indicate SEM. The number of animals used is indicated by "n" (E) or is given in parentheses (A, B, F).