Figure 3. Effect of conditional or constitutive inactivation of Hif‐1α on the hypoxic ventilatory response in mice before and after ventilatory acclimatisation to chronic hypoxia .

Minute ventilation before, during and after an acute hypoxic exposure to 10% oxygen with 3% carbon dioxide (open bars). Comparisons were tamoxifen‐treated Hif‐1α^f/f;CreER versus Hif‐1α^f/f littermates (n = 7 pairs)(A–D); Hif‐1α^+/− versus wild‐type littermates (n = 6 pairs) (E–H). Animals were studied immediately before (0 h, A, E) or after (48 h, B, F; 7 days, C, G) exposure to chronic hypoxia (CH). D and H, hypoxic ventilatory responses (HVR) calculated from changes in minute ventilation before and after exposure to CH for the indicated times. For mice bearing the conditionally inactivated allele, HVR values are shown before and after tamoxifen (TMX). Values shown are mean ± SEM.