[Induction of HSP70 mRNA in the brain and liver of rats after scalding]

Induction of hsp70 mRNA in rats after scalding was analysed using 32P labeled hsp70 cDNA. The results showed that the expression of hsp70 mRNA in brain and liver was induced markedly after scalding. Time course of the increase showed that induction took place within 5 min and subsided 24 h after scalding. In the liver, induction took place still earlier, i.e. within 1 min and lasted for more than 24 h. The induction of hsp70 mRNA in rats after scalding did not seem to be due to elevation of core temprature since the increase of temperature of rat brain and liver after scalding was not more than 1 degree C. Western blot anlyses further showed that the induction of hsp70 occured within 5 min and lasted for more than 3 h in the brain of rats after scalding. The above results demonstrated that the hsp expression in internal organs could be induced by local injuries and was not necessarily dependent upon the direct effect of stimuli in intact animals.