title: Relative accretion of 99mTc-polyphosphate by forming and resorbing bone systems in rats: its significance in the pathologic basis of bone scanning.
abstract: The relative roles of osteogenesis andd osteolysis in the production of positive radionuclide images of skeletal lesions were investigated. The uptake of 99mTc-polyphosphate (Tc-PP) by each process was measured in an animal model that permitted bone formation and resorption to be studied independently. Ten rats received intramuscular implants of bone-forming demineralized matrix (DM) and resorbing devitalized bone (DV). Radiographs and Tc-PP scintiscans were made each week thereafter. At 6-10 weeks, the implants and normal bone samples were removed, counted for 99mTc, and examined histologically. The uptake of Tc-PP BY DM implants was first detected on images made 3 weeks after implanatation, and by DV implants, 1-2 weeks later. Serial radiography showed progressive calcification of DM an resorption of DV implants. Microscopic examinations of undecalcified sections, stained with a modified Goldner preparation, revealed vital-bone formation in the DM implants and osteoclastic resorption in the DV. Activity counts per gram of DM and DV implants were, respectively, 200% and 90% that of normal bone. Since only the bone-forming system (DM) accumulated Tc-PP at greater than normal concentrations, this study indicates that positive bone images of osteolytic lesions solely reflect compensatory osteogenic responses.
mesh_terms: D000818:Animals; D001847:Bone Diseases / Q000175:diagnosis*; D001862:Bone Resorption; D005260:Female; D008297:Male; D010012:Osteogenesis; D010014:Osteolysis; D010710:Phosphates; D011877:Radionuclide Imaging; D051381:Rats; D013667:Technetium
chemical_list: D010710:Phosphates; D013667:Technetium