Immunohistochemical detection of alkaline phosphatase in formalin-fixed and paraffin-embedded rat liver

Alkaline phosphatase (ALP) in rat liver was detected by means of immunohistochemical techniques in ordinary histologic specimens which were fixed with formalin and embedded in paraffin. The specimens were incubated in anti-ALP antibody at room temperature for a longer time, 3hr, than ordinary incubation time. Antigen detection sensitivity and contrast of reaction product of the immunogold silver staining were superior to those of the peroxidase-labeled antibody method. In rat livers which were partially hepatectomized 24 hr before, the more abundant enzyme localized around enlarged bile canalicular spaces.