Adaptive stabilization of structures and adaptive protection of the heart in rats of two different genetic strains: Role of heat-shock proteins hsp 70

Periodic exposures of Wistar rats to a stressor resulted in the accumulation of five isoforms of heat-shock proteins (hsp70) in their myocardia and, as a consequence, in increased resistance to thermal damage shown by their isolated hearts, whereas in rats of the August strain such exposures did not lead to hsp70 accumulation and the heart's resistance was not increased. It is concluded that the ability of a given genetic strain to develop adaptive protection of the heart appears to depend on the ability of that strain to boost the expression of hsp70 genes in response to stressors.