Paraformaldehyde-fixed, paraffin embedded rat liver; Antigen retrieval by boiling in sodium citrate buffer (pH6.0) for 15min; Block endogenous peroxidase by 3% hydrogen peroxide for 20 minutes; Blocking buffer (normal goat serum) at 37°C for 30min; Antibody incubation with IHH Polyclonal Antibody, Unconjugated (bs-6624R) at 1:500 overnight at 4°C, followed by a conjugated secondary for 20 minutes and DAB staining.