Fig. 1.

Experimental design. Brown Norway 9- to 12-wk-old male rats were exposed to 43 days of normoxia (NORM) or chronic intermittent hypoxia (CIH), concurrent with house dust mite (HDM) sensitization (S) on days 1 and 3. On day 7, and weekly thereafter, animals were challenged (C) with intratracheal HDM or saline (SAL) instillations. On day 43, blood pressure was measured, and the animals were returned to their exposure chambers. On the morning of day 44, the animals were removed from the chambers for end-point [pulmonary function testing (PFT) , blood for serum cytokines and IgE levels, and heart extraction] collection.