Figure 3
From: Life-long brain compensatory responses to galactic cosmic radiation exposure
Enhancement in Schaffer collateral-CA1 LTP and recovery of spatial learning deficits six months after exposure to 56Fe particle radiation (a, b) Time course and magnitude (inset bar graph) of LTP in slices from mice exposed to 10 cGy, 50 cGy, or 100 cGy radiation, compared to sham-irradiated controls (0 cGy). After a 15 min baseline, LTP was elicited by two high-frequency TBS stimulus trains (arrows), and magnitude of LTP between 35–40 min post TBS (perforated box) was compared across doses in (a) male mice, One-way RM ANOVA, F(1.95,19.45) = 820.8, P < 0.0001, Tukey’s post hoc test: 0 cGy vs. 50 cGy, P < 0.0001; 0 cGy vs. 100 cGy, P < 0.0001, 50 cGy vs. 100 cGy, P < 0.0001 and (b) female mice, One-way RM ANOVA, F(1.30,12.95) = 393.0, P < 0.0001, Tukey’s post hoc test: 0 cGy vs. 50 cGy, P < 0.0001; 0 cGy vs. 100 cGy, P < 0.0001, 50 cGy vs. 100 cGy, P < 0.0001. *P < 0.05 compared to 0 cGy, n = 12–16 slices per dose per sex. (c) Representative paired-pulse responses of population compound action potentials elicited in slices from a male sham-irradiated mouse, taken at 10 and 500 ms inter-stimulus interval. (d) Mean paired-pulse profiles across inter-stimulus intervals in all slices from control (0 cGy) and irradiated (100 cGy) mice. Each point represents mean ± SEM. n = 12–16 slices per dose per sex. (e, f) Learning curves, including pretraining, training days 1–3, and conflict training days 1–2, are shown for (e) male mice, Two-way RM ANOVA, dose: F(1,8) = 0.59, P = 0.59, trial: F(2.43,19.43) = 18.88, P < 0.0001; interaction: F(5,40) = 0.993, P = 0.434, (Tukey’s post hoc test did not reveal significant within treatment effect) and (f) female mice, Two-way RM ANOVA, dose: F(1,8) = 0.99, P = 0.99; trial: F(1.96,15.66) = 31.54, P < 0.0001; interaction: F(5,40) = 1.896, P = 0.117, (Tukey’s post hoc test did not reveal significant within treatment effect), as a function of normalized number of entries into the stationary shock zone (Errors). n = 5 mice per dose per sex. Each point represents mean errors normalized to pre-training entries ± SEM.
