https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Some mechanisms of reflex control of the circulation by the sympatho-adrenal system https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:12690 Thu 26 Sep 2024 14:52:41 AEST ]]> The effects of chloralose urethane and sodium pentobarbitone anaesthesia on the local and autonomic components of the circulatory response to arterial hypoxia. https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:12725 Sat 24 Mar 2018 08:18:26 AEDT ]]> Local and reflex factors affecting the distribution of the peripheral blood flow during arterial hypoxia in the rabbit https://ogma.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 Tb 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 Tb response, phase I, was a disappearance of circadian rhythm and a fall in Tb to 36.3 ± 0.52°C. In phase II, Tb increased to a peak of 38.7 ± 0.64°C. In phase III, Tb gradually decreased. At reoxygenation at the end of the hypoxic period, phase IV, Tb increased 1.1 ± 0.25°C. Before hypoxia, Lₐ decreased 70% from its nocturnal peak to its diurnal nadir and was entrained with Tb. 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 Tb and Lₐ throughout the hypoxic exposure, 2) the hypoxia-induced changes in Tb and Lₐ are independent of each other and of the circadian clock, and 3) the Tb response to hypoxia at thermoneutrality has several phases and includes both hypothermic and hyperthermic components.]]> Sat 24 Mar 2018 08:15:49 AEDT ]]>