Figure 6. The X-Irradiation Impairment in One-Shock CFC Is Paralleled by Decreased CA3 Reactivation, and Both Impairments Can be Rescued by Using a Three-Shock CFC Paradigm.

(A) Experimental design

(B) In one-shock CFC, context-elicited freezing was significantly reduced in x-irradiated mice (F(1,22) = 4.509, p < 0.05) (n = 11–13 mice per group). In three-shock CFC, context-elicited freezing was comparable in both groups (F(1,25) = 1.063, p = 0.31) (n = 13–14 mice per group).

(C and D) The number of DCX⁺ cells was significantly reduced in x-irradiated mice.

(E and F) In the one-shock CFC cohort, (E) the number of EYFP⁺ and (F) Arc⁺ DG cells was similar.

(G) Both groups had a comparable percent of colabeled EYFP⁺/Arc⁺ cells.

(H and I) The number of (H) EYFP⁺ and (I) c-fos⁺ CA3 cells was similar.

(J) X-irradiated mice had a significantly smaller percent of colabeled EYFP⁺/c-fos⁺ CA3 cells (p < 0.01).

(K–M) In the three-shock CFC cohort, (K) the number of EYFP⁺ and (L) Arc⁺ cells and (M) the percent of colabeled EYFP⁺/Arc⁺ DG cells did not differ between the groups.

(N–P) In CA3, the number of (N) EYFP⁺ and (O) c-fos⁺ cells and (P) the percent of colabeled EYFP⁺/c-fos⁺ cells did not differ between the groups. Error bars represent ± SEM.