Thermoregulation, respiration quotient and key antioxidant enzyme activities in the liver and heart of rats under hypergravity stress

1Muradian, Kh.K, 1Timchenko, AN, 1Utko, NA, 1Badova, TA, 1Bezrukov, VV
1State Institution "D.F.Chebotarov Institute of Gerontology of the National Academy of Medical Sciences of Ukraine", Kyiv, Ukraine
Kosm. nauka tehnol. 2004, 10 ;(1):099-104
Publication Language: Russian
Effects of mild hypergravity stress (2g) on respiration quotient, body temperature and coefficient of thermoconductivity, as well as activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase in the liver and heart of male Wistar rats are studied. Hypergravity stress, modelled by centrifugation, induced a significant decline of body temperature which reached the minimal level at 2-4 h and almost returned to the normal values within 3 h of the post-hypergravity recovery period. Thermoconductivity exhibited almost opposite dynamics, namely, increase followed by normalization. Results of linear regression and correlation analyses demonstrated positive correlation between body temperature and Vo2 during  the both  phases of body temperature  decrease and

recovery. Respiration quotient declined progressively within the whole investigated period, which can be a result of enhancing thermogenesis due to preferential oxidation of fatty acids. The data of 3D non-linear plotting indicated that body temperature could be higher in the individuals which manage quicker switching on fatty acid oxidation during the centrifugation.

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