https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:12690 Sat 24 Mar 2018 08:16:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:12669 b) and Lₐ. After habituation for 7 days to 29°C and 12:12-h dark-light cycles, 48 h of baseline data were acquired from six control and four experimental rats. The mean T_b for the group oscillated from a nocturnal peak of 38.4 ± 0.18°C (SD) to a diurnal nadir of 36.7 ± 0.15°C. Then the experimental group was switched to 10% O₂ in N₂. The immediate T_b response, phase I, was a disappearance of circadian rhythm and a fall in T_b to 36.3 ± 0.52°C. In phase II, T_b increased to a peak of 38.7 ± 0.64°C. In phase III, T_b gradually decreased. At reoxygenation at the end of the hypoxic period, phase IV, T_b increased 1.1 ± 0.25°C. Before hypoxia, Lₐ decreased 70% from its nocturnal peak to its diurnal nadir and was entrained with T_b. With hypoxia Lₐ decreased in phase I to essential quiescence by phase II. Lₐ had returned, but only to a low level in phase III, and was devoid of any circadian rhythm. Lₐ resumed its circadian rhythm on reoxygenation. We conclude that 63 h of sustained hypoxia 1) completely disrupts the circadian rhythms of both T_b and Lₐ throughout the hypoxic exposure, 2) the hypoxia-induced changes in T_b and Lₐ are independent of each other and of the circadian clock, and 3) the T_b response to hypoxia at thermoneutrality has several phases and includes both hypothermic and hyperthermic components.]]> Sat 24 Mar 2018 08:15:49 AEDT ]]>