STUDIES ON CIRCULATION OF EXPERIMENTAL TUMOURS .I. EFFECT OF INDUCED FIBRINOLYSIS AND ANTIFIBRINOLYSIS ON CAPILLARY BLOOD FLOW AND CAPILLARY TRANSPORT FUNCTION OF 2 EXPERIMENTAL TUMOURS IN MOUSE

1. 1. In two transplanted experimental tumours in the mouse (mammary carcinoma and 20-methylcholanthrene induced sarcoma) studies were carried out on the capillary blood flow and the capillary transport function of the tumour vasculature by measuring simultaneously the clearance of two locally injected radioactive isotopes, 133Xe and 24Na. 2. 2. Results indicated a wide spread of flow values from animal to animal for both tumours, but despite this fact relatively uniform transport characteristics. 3. 3. Fibrinolysis was induced with plasmin and antifibrinolysis with tranexamic acid in two additional groups of animals with the transplanted tumours. Neither procedure altered the blood flow or the transport characteristics of either tumour. 4. 4. It is concluded that the previously observed effects of plasmin and tranexamic acid on the growth rate and spontaneous metastasis formation of these two tumours in the mouse are not due to changes in tumour circulation. © 1969.