EFFECT OF ACUTE HEAT-STRESS ON HEAT-SHOCK PROTEIN-70 MESSENGER-RNA AND ON HEAT-SHOCK PROTEIN EXPRESSION IN THE LIVER OF BROILERS

1. The synthesis of heat shock protein 70 (Hsp70) mRNA and the express ion of Hsp70 in the liver of broiler chickens submitted to acute heat stress (35 degrees C for 5 h) was investigated. 2. Hsp70 expression wa s detected by SDS-PAGE and Western blot analysis using a polyclonal an tiserum against Hsp70 of Blastocladiella emersonii. The specific signa l of Hsp70 mRNA was analysed by Northern blot using as probe a Hsp70 c DNA of B. emersonii. 3. An increase in the amount of Hsp70 was detecte d from the first up to the fifth hour of acute heat exposure. This inc rease in the amount of Hsp70 was accompanied by an increase in Hsp70 m RNA which peaked at 3 h. 4. This study shows that the heat induced inc rease in Hsp70 mRNA and protein in broiler liver, in vivo, are time de pendent, similar to that in mammals.