RESUMO
<p><b>OBJECTIVE</b>To evaluate the inhibitory effect of small interfering RNA (siRNA) targeting HBV C gene region on hepatitis B virus (HBV) in vivo.</p><p><b>METHODS</b>An animal model of HBV infection was developed hydrodynamically, and pcDNA3.1-HBV and siRNA were together injected into the tail vein of the BALB/c mice. HBsAg was analyzed by time-resolved immunofluorometric assay, HBV DNA was analyzed by fluorogenic quantitative PCR (FQ-PCR), HBV C-mRNA was detected by semi-quantitative RT-PCR, and viral specific proteins (HBsAg and HBcAg) in the mice livers were assayed using immunohistochemical staining.</p><p><b>RESULTS</b>In the mice, the siRNA effectively inhibited HBV replication and expression compared with the controls. The inhibitive effect of siRNA on HBV lasted at least 3 days.</p><p><b>CONCLUSION</b>These results demonstrate that RNAi can substantially inhibit HBV replication and expression in vivo.</p>