Objective To investigate the expressions of P56

IFN-β

IFN-α mRNAs and the effects of KPV

a COOHterminal tripeptide sequence of alphamelanocyte stimulating hormone [alpha-MSH(11-13)]

and anaesthesia on the expressions in severe burn injured mice.  Methods Eighty mice were randomly and equally divided into 4 groups: control

burn (TBS15%Ⅱ)

burn+KPV (injection of 40 μg per animal immediately after burn)

and burn+anaesthesia (injection of 0.4 mg/kg diazepam and 10 mg/kg ketamine immediately after burn). All animals were sacrificed in 3 h after burn respectively. The expressions of P56

IFN-β

and IFN-α mRNAs in liver

spleen

lung and kidney tissues were detected with RT-PCR.  Results P56 was expressed highly in liver

spleen

lung

and kidney in normal control group

and was obviously increased in kidney in burn group and burn+KPV group

but that in burn+anaesthesia group had no significant difference with that in normal control. IFN-β was not expressed in live and lightly expressed in spleen

lung and kidney

and its expression in lung was significantly increased in burn group and burn+anaesthesia group

but mildly decreased in burn+KPV group. IFN-α mRNA was expressed in all detected organs in normal control

and highly expressed in kidney of burn group and burn+KPV group

but not in burn+anaesthesia group.  Conclusion These results indicate that the increased IFN expressing induce the up-regulation of P56

suggesting which may be involved in the disorder of early post trauma stress.