PMC

Localization of HIF-1α by immunofluorescent staining. Immunofluorescently labeled cells in the cortex of representative Wt (a–d) and HIF-1α^Δ/Δ (e–h) brains 24 h after HI at P7. a, e NeuN. b, f HIF-1α. c, g Merged NeuN and HIF-1α. Yellow cells indicate localization of HIF-1α, where present, to neurons. d, h NeuN, HIF-1α and DAPI for visualization of nuclei.

HI brain injury 5 days after HI. a Total brain injury score (scale 0–24). HIF-1α^Δ/Δ mice (median 14, n = 11) are more injured than Wt (median 11, n = 27) (∗p < 0.05). b Cortical injury (scale 0–9). HIF-1α^Δ/Δ cortices (Ctx) (median = 6) are more injured than Wt cortices (median = 4) (∗p < 0.01). c Hippocampal injury (scale 0–12). There is no difference in hippocampal injury between groups (median = 7 for both, p 1 0.75). The horizontal line within the box represents the median injury score for each group. Analysis by the Mann-Whitney test. HC = Hippocampus.

HIF-1α protein expression. a HIF-1α protein expression in P7 mouse cortices, with or without 1 h of 8% oxygen exposure, by Western blot analysis. Optical densities are normalized to β-actin and values are expressed as mean ± SD of optical densities normalized to Wt control (Ctrl). HIF-1α protein expression is higher in hypoxic Wt (∗) compared to all other groups: Wt naïve control (p < 0.05), HIF-1α ^Δ/Δ naïve control (p < 0.01), and HIF-1α ^Δ/Δ hypoxia (p < 0.04). In addition, HIF-1α^Δ/Δ with hypoxia has higher HIF-1α protein levels than HIF-1α^Δ/Δ control (∘ p < 0.05). For Wt control, Wt hypoxia and HIF-1α^Δ/Δ, n = 3; for HIF-1α^Δ/Δ hypoxia, n = 5. Analysis by ANOVA with the Bonferroni multiple comparison test. b HIF-1α protein expression in mouse cortices 24 h after HI at P7. The Wt cortex ipsilateral (ipsi) to HI injury (∗n = 5) has increased HIF-1α protein expression compared to all other groups: Wt contralateral (ctra) to HI (p < 0.01, n = 5) Wt sham (p < 0.01, n = 7), HIF-1α^Δ/Δ sham (p < 0.01), HIF-1α^Δ/Δ ipsilateral to HI injury (p < 0.01) and HIF-1α^Δ/Δ contralateral to HI injury (p < 0.001). There are no significant differences among the three HIF-1α^Δ/Δ groups. However, there is a trend for higher HIF-1α protein expression in the HIF-1α^Δ/Δ cortex ipsilateral to HI injury (n = 9) compared to HIF-1α^Δ/Δ sham (p < 0.06, n = 4) and contralateral to HI (p = 0.10, n = 9). Optical densities are normalized to β-actin and values are expressed as optical densities normalized to Wt sham (mean ± SD). Analysis by ANOVA with the Bonferroni multiple comparison test.