Labeling and testing of 99mTc-streptokinase for the diagnosis of deep vein thrombosis.
A detailed study has been made of the method for labeling streptokinase with 99mTc in order to get a radioactive indicator for rapid scintigraphic visualization of thrombi and emboli. The best method found for preparing 99mTc-streptokinase was by reducing 99mTc-pertechnetate with  2 mumole SnCl2 at pH 0.7 and then adding 50,000-75,000 IU of streptokinase at a final pH of about 2. After 1 hr of equilibration the labeling efficiency was 75-80% as determined by the method of gel chromatography column scanning. The dynamic behavior and distribution of 99mTc-streptokinase in different organs was studied in rabbits where a high uptake was found in liver. In a clinical investigation using 99mTc-streptokinase prepared according to this work, however, the liver uptake in man was only 10-20%.
D000818:Animals; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D008099:Liver / Q000378:metabolism; D011817:Rabbits; D011877:Radionuclide Imaging; D013300:Streptokinase / Q000378:metabolism; D013667:Technetium / Q000378:metabolism; D013924:Thrombophlebitis / Q000175:diagnosis*
D013667:Technetium; D013300:Streptokinase