INDICES OF OXYGEN TRANSPORT, UTILIZATION, AND STORAGE IN RATS ACCLIMATED TO ALTITUDE AT DIFFERENT TEMPERATURES,

Oxygen transport, utilization, storage, and related functions were studied in rats exposed to simulated altitude 18,000 feet at three different temperatures 5, 24, and 36 C. for periods in excess of 3 months. Liver, heart, kidney, and adrenal weights were altered only when thermal influences were involved. Adrenal weight under conditions of altitude-cold was greater than in cold alone. The oxygen transport function was normal in altitude-cold environment, but it was depressed in altitude-heat environment. While liver succinic dehydrogenase activity was elevated in all altitude groups, its elevation was more noticeable in the groups exposed to heat and cold. In the adrenals, succinic dehydrogenase activity showed greatest elevation in altitude-cold exposure. Oxygen storage was unaffected by thermal factors. Author