2012
Volume 12, Number 4, pp. 133–137
Whole body hyperthermia and the phenomenon of temperature homeostasis in the rat brain
Nodar Mitagvaria,1James Bicher,2 Marina Devdariani,1 Lia Davlianidze,1 Marina Nebieridze1 and Nana Momtselidze1
1 I. Beritashvili Centre of Experimental Biomedicine, Tbilisi, Georgia
2 Bicher Cancer Institute, Los Angeles, California
The aim of this study was to determine the temperature changes in rat brain tissue caused by whole body hyperthermia. Analysis of the results lead to the inference that the brain has a tightly controlled system of temperature autoregulation with respect to exogenous temperature changes. The upper limit of this autoregulation (for rats, at least) is marked by an environmental temperature of about 45 C. Nitric oxide has an important rôle in the normal functioning of the brain temperature autoregulation system. Behavioral disorders observed in animals after whole body hyperthermia (within the range of brain temperature autoregulation) is not associated with changes in temperature of the central nervous system, but rather is mediated by impaired blood circulation and oxygen supply to the brain tissues caused by rapid deterioration of blood rheological properties.