HIF-1α expression in primary cortical neurons exposed to hypoxia/ischemia. A & A’) Neurons were double-stained for HIF-1α and MAP2 in the presence of 5 and 25 mM glucose with and without hypoxia. HIF-1α expression in the somata was observed in cells with interneuron-like morphology after hypoxia. B) CoCl2 (0.3 mM) induced HIF-1α expression in cells with interneuron-like morphology. C) Quantification represents the increase in HIF-1α–ir staining (mean ± SD; 5-10 neurons quantified from each experiment, n = 3 experiments). D) In vivo brain slice shows a similar pattern of positive HIF-1α -ir in round soma (open arrow) and negative in neurons with pyramidal-like morphology (solid arrow) in the ipsilateral side. *p < 0.05, compared with normoxia (25 mM glucose), #p < 0.05, compared with hypoxia (25 mM glucose). Scale bars, 20 μm (A, A’, B); 10 μm (D).