Levels of GSH in cortical neurons exposed to hypoxia. A) During hypoxia, GSH increased in MAP2-ir neurons with round somata (bottom panel, open arrow) and decreased in neurons with pyramidal-like morphology (upper panel, solid arrow). B) GSH increased in a subset of GAD65/67–ir neurons exposed to hypoxia (bottom panel, open arrow). C) Elevated HIF-1α expression in GAD65/67–ir neurons containing high levels of GSH when exposed to hypoxia (middle panel). BSO treatment decreased HIF-1α expression in GAD65/67-positive neurons during hypoxia. D) Percentages of HIF-1α-expressing GAD65/67-ir neurons expressing a high level of GSH and GAD65/67-ir neurons expressing a low levels of GSH and HIF-1α (mean ± SD; n = 3). The “low” level referred to the level of GSH in normoxic GAD65/67 neurons that was normalized to 1. The “high” level referred to the elevated GSH level in GAD65/67 neurons with a mean of 1.40 ± 0.10. E) Total MCB-GSH intensity in GAD65/67-positive neurons with and without BSO after hypoxia (mean ± SD; 8-10 neurons quantified from each experiment, n = 3 independent cultures). Scale bars, 20 μm.