Abstract
High acid phosphatase activity was observed in osteoclasts of several species using a reproducible azo-dye technique.
High activity of two distinct enzymes, acid and alkaline phosphatase, are associated with osteoclasts and osteoblasts respectivey.
Althouth frozen-dried tissues are recommended for definitive studies, the enzyme techniques used give satisfactory results with cold acetone-fixed tissues. The most accurate localization of acid phosphatase in osteoclasts in controlled comparative studies is obtained with double-embedded frozen-dried undecalcified tissues in conjunction with naphthol AS-phosphates.