Research Paper Volume 13, Issue 12 pp 15815—15832

Spatiotemporal dynamics of γH2AX in the mouse brain after acute irradiation at different postnatal days with special reference to the dentate gyrus of the hippocampus

γH2AX immunostaining counterstained with hematoxylin shows very few γH2AX foci in different brain regions of postnatal day 4 (P4) mice without irradiation including dorsal pallium(DPall) /isocortex layer I (DPall-I) and pia mater (A), DPall –II (B, arrow), central subpallium/classic basal ganglia (CSPall) striatum (C) and corpus callosum (D). However, acute irradiation with 5Gy at P3 induced very significant γH2AX expression in the entire brain 1 day after radiation exposure or P4 mice. γH2AX foci could be observed in almost all brain regions at 1 day after irradiation at P3, including DPall-I (A’, A” is magnified from the ellipse in A’), DPall-II to DPall-VI of the grey mater (B’, B”, DPall-II, B” is magnified from the ellipse in B’), CSPall striatum (C’, C” is magnified from the ellipse in C’) and corpus callosum (D’, D” is magnified from the ellipse in D’) at 1 day after irradiation at P3. Scan bar=50μm in (A) applies to (B–D) (A’–D’) Scan bar=25μm in (A”) applies to (B” –D”).

Figure 1. γH2AX immunostaining counterstained with hematoxylin shows very few γH2AX foci in different brain regions of postnatal day 4 (P4) mice without irradiation including dorsal pallium(DPall) /isocortex layer I (DPall-I) and pia mater (A), DPall –II (B, arrow), central subpallium/classic basal ganglia (CSPall) striatum (C) and corpus callosum (D). However, acute irradiation with 5Gy at P3 induced very significant γH2AX expression in the entire brain 1 day after radiation exposure or P4 mice. γH2AX foci could be observed in almost all brain regions at 1 day after irradiation at P3, including DPall-I (A’, A” is magnified from the ellipse in A’), DPall-II to DPall-VI of the grey mater (B’, B”, DPall-II, B” is magnified from the ellipse in B’), CSPall striatum (C’, C” is magnified from the ellipse in C’) and corpus callosum (D’, D” is magnified from the ellipse in D’) at 1 day after irradiation at P3. Scan bar=50μm in (A) applies to (BD) (A’–D’) Scan bar=25μm in (A”) applies to (B” –D”).