title: Mechanistic aspects of the interaction of 99mTc in association with stannous pyrophosphate with damaged red blood cells.
abstract: The binding of the various components of [99mTc] stannous pyrophosphate and stannous pyrophosphate/pertechnetate to damaged red blood cells is studied. It is shown that the pyrophosphate molecule enters the damaged red blood cells when the pyrophosphate concentration in blood is greater than 100 nmol/ml but does so as the uncomplexed ion. Uptake of 99mTc when introduced as [99mTc]stannous pyrophosphate is constant at approximately 18%. If the 99mTc is introduced as pertechnetate after the damaged cells are mixed with stannous pyrophosphate then at low stannous ion concentrations the uptake is directly dependent on the stannous ion concentration. However, at higher stannous ion concentrations the uptake of technetium by the damaged red cells decreases, but this decrease appears to result from several independent aspects of the sample, such as the binding of the technetium to the plasma proteins and the displacement of the technetium by pyrophosphate within the damaged cell.
mesh_terms: D004912:Erythrocytes; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D007553:Isotope Labeling; D011122:Polyphosphates; D013670:Sodium Pertechnetate Tc 99m; D013667:Technetium; D016698:Technetium Tc 99m Pyrophosphate; D014003:Tin Polyphosphates
chemical_list: D011122:Polyphosphates; D014003:Tin Polyphosphates; C017742:technetium Tc 99m stannous pyrophosphate; D016698:Technetium Tc 99m Pyrophosphate; D013667:Technetium; D013670:Sodium Pertechnetate Tc 99m