title: In vitro interaction between 99Tcm-labeled pyrophosphate, 32P-labeled pyrophosphate and rat tissues.
abstract: Whole-body sections from young rats were incubated with solutions containing 32P-labeled pyrophosphate, 99Tcm-labeled pyrophosphate and 99Tcm-pertechnetate, respectively, at pH 7.6 or pH 8.6. After incubation, the sections were used for autoradiography and/or staining in order to visualize tissue affinity for 99 Tcm and areas of pyrophosphatase activity. At pH 7.6, the distribution patterns of 99Tcm-labeled pyrophosphate and 32P-labeled pyrophosphate were similar. When pH was raised to 8.6, 99Tcm-labeled pyrophosphate was degraded before reaching the tissues and their enzymes. The distribution pattern of 99Tcm-labeled pyrophosphate at pH 8.6 was similar to that of 99Tcm-pertechnetate. 32P-labeled pyrophosphate could serve as a substrate for alkaline pyrophosphatase and the enzyme activity was demonstrated autoradiographically.
mesh_terms: D000818:Animals; D001345:Autoradiography; D001842:Bone and Bones / Q000000981:diagnostic imaging; D011756:Diphosphates; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D010761:Phosphorus Radioisotopes; D011877:Radionuclide Imaging; D051381:Rats; D013667:Technetium
chemical_list: D011756:Diphosphates; D010761:Phosphorus Radioisotopes; D013667:Technetium