Activity of citrate synthase (A), cytochrome-c oxidase (complex IV - B), and complex I (C) measured on brain cortex samples in ovariectomized female rats treated with vehicle (Veh), the ERα (PPT), or the ERβ (DPN) agonist and exposed to room air (AIR) or chronic intermittent hypoxia (CIH). All data are box and whiskers (median, 25th and 75th percentiles, min and max values) † : p<0.01, vs Veh AIR.