[Dynamics of the changes in various integral indices of the functional state of the body of white rats during the prolonged action of x-radiation and external heat].

Effects of low doses of X-radiation (0.02 Gr. a session, for 25 days), external heat (daily 4-h exposure in a thermochamber at 37.0 degrees C) and combined (consecutive) action of these factors on mature Wistar male rats were studied. Experimental animals were somewhat behind in body mass increment during exposure to the physical factors as compared to control rats. Radiation promoted a rise in rectal temperature, external heating to its small decrease, while combined exposure to the factors levelled the effects. There were certain changes in the CNS, as indicated by a small increase in the summation-threshold index. The heart rate did not significantly change. The changes normalized within 1-5 weeks after cessation of the exposures.