Objective    To investigate the effect of HO-1 on acute rejection after orthotopic liver transplantation (OLT) in rats.      Methods    Taking dark agouti (DA) rats as donors and Lewis rats as recipients

OLT was performed. Before OLT

the DA rats and Lewis rats were matched in pairs

and divided into control group

ZnPP group and CoPP group

the paired rats of which intraperitoneally received normal saline

20 mg/kg ZnPP and 5 mg/kg CoPP respectively 24 h before OLT. Ten pairs of rats were in each group. On day 3 or 7 after OLT

recipient rats were killed

then blood sample and liver specimen were collected. Plasm levels of aspartate aminotransferase (AST)

alanine aminotransferase (ALT)

total bilirubin (TBIL)

albumin (ALB) were measured; HE staining and MPO staining were performed; The expression of HO-1 was detected by the fluorence real time RT-PCR.     Results    On day 3 and 7 after OLT

AST

ALT and TBIL showed significant statistical significance among the three groups; ALB was highest in CoPP group

then in control group

lowest in ZnPP group. On day 3 after OLT

control group had acute rejection of degree one to degree two

ZnPP group had acute rejection of degree two; CoPP group mainly had acute rejection of degree one; On day 7 after OLT

control group mainly had acute rejection of degree two; ZnPP group had acute rejection of degree two to degree three; CoPP group had acute rejection of degree one to two. The expression of HO-1 was highest in CoPP group

then control group

and lowest in ZnPP group.     Conclusion    The expression of HO-1 in OLT with acute rejection in rats can palliate the acute rejection.