Showing papers by "Jon E. Wergedal published in 1969"
TL;DR: The distribution of acid and alkaline phosphatase activity in the rat tibia has been studied in transverse sections sawed from fresh undemineralized diaphyses and a zone of activity was found at the mineralizing front where mineralization is initiated.
Abstract: The distributionofacidand alkaline phosphatase activity in the rat tibia has been studied intransversesectionssawed from freshundemineralized diaphyses.The endostealresorbingsurfaceshad thehighestacidphosphatase activityas demonstrated with50 mMa-naphtholphosphate as the substrate.Strong activitywas present not only in osteoclastsand adjacent osteocytes but extracellularly lining Howship’s lacunae. In areas of bone formation, moderate acid phosphatase activity was present in osteoblasts and young osteocytes. In addition, a zone of activity was found at the mineralizing front where mineralization is initiated. This active zone (a) was separated from the active periosteal cell layer by a zone of inactive osteoid and (b) in formol-calcium-fixed demineralized sections extended into young bone. The identity of the mineralizing front was confirmed by tetracycline labeling. The activity at the mineralizing front had the properties of an enzyme. Alkaline phosphatase activity demonstrated with naphthol ASTR phosphate was largely associated with the osteoblasts and other mesenchymal cells at forming surfaces.
99 citations