title: Alkaline fixation-resistant acid phosphatases in human tissues: histochemical evidence for a new type of acid phosphatase in endothelial, endometrial and neuronal sites.
abstract: The effect of pH during formalin fixation on acid phosphatases in human tissues was studied. Lysosomal-type acid phosphatase was sensitive to alkaline fixation, being completely inactive after fixation at pH 9.0. Prostatic and tartrate-resistant osteoclastic/macrophagic types were alkaline fixation-resistant, as was an acid phosphatase localized in endothelium, endometrial stromal cells and intestinal nerves. The latter activity was further separable into fluoride- and tartrate-sensitive beta-glycerophosphatase and fluoride-sensitive, tartrate-resistant alpha-naphthyl phosphatase. The activities appeared to represent either different, tightly associated enzymes or separate activity centres of a single enzyme. Alkaline fixation-resistant alpha-naphthyl phosphatase at endothelial, endometrial and neuronal sites was also well demonstrated in unfixed or neutral formalin-fixed sections as tartrate-resistant activity similar to classical tartrate-resistant acid phosphatase, but these phosphatases appear to be antigenically different. Alkaline fixation-resistant acid phosphatase showed a restricted tissue distribution both in endothelium (mainly in vessels of abdominal organs) and at neuronal sites (only in intestinal nerves). Alkaline fixation-resistant acid phosphatase appears to represent a previously unknown or uncharacterized enzyme activity whose chemical properties could not be classified as any previously known type of acid or other phosphatases.
authors.affiliation: Department of Pathology, Helsinki University Central Hospital, Espoo, Finland.
authors.forename: S
authors.initials: S
authors.lastname: Partanen
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis / Q000145:classification / Q000378:metabolism*; D004717:Endometrium / Q000737:chemistry / Q000201:enzymology*; D004730:Endothelium, Vascular / Q000737:chemistry / Q000201:enzymology*; D005260:Female; D005404:Fixatives; D006651:Histocytochemistry; D006801:Humans; D008247:Lysosomes / Q000737:chemistry / Q000201:enzymology; D008264:Macrophages / Q000737:chemistry / Q000201:enzymology; D008297:Male; D009474:Neurons / Q000737:chemistry / Q000201:enzymology*; D010920:Placenta / Q000098:blood supply; D011247:Pregnancy
chemical_list: D005404:Fixatives; D000135:Acid Phosphatase