[The heparin-dependent inhibition of the accumulation of 131J-fibrinogen in the solid form of Walker-256-carcinosarcoma of the rat (author's transl)].

The intravenous injection of 131J-fibrinogen results in a selective accumulation of radioactivity in the solid Walker-256-carcinosarcoma of the rat. An effective anticoagulation with heparin beginning before administration of the radio-iodinated fibrinogen and continued up to the end of the experiment inhibits the enrichment of radioactivity. It is supposed that the radioactivity in the tumor is correlated to the deposition of 131J-fibrin. A clotting process in tumor transforms both fibrinogen and 131J-fibrinogen to fibrin resp. 131J-fibrin. This conversion is thrombin-dependent might be blocked by heparin. The tumor growth is not influenced by the presence of heparin.