EFFECTS OF VARIOUS VASOACTIVE AGENTS ON TUMOR BLOOD FLOW IN RAT

Effects of angiotensin Ⅱ and other six vasoactive agents on tissue blood flow of Yoahida rat ascites hepatoma AH109A and normal liver were measured by the hydrogen clearance method. The mean blood flow in the tumor peripheral part under normal tension was 11. 9±8. 2ml/ min/100g tissue and was not influenced by tumor size. Tumor blood flow was more significantly increased in infusion angiotensin Ⅱthan 0.5mg/ ml methoxamine, however, normal liver blood flow of tumor-bearing rats was unchanged in contrast to an Increase seen in the tumor. A pronounced reduction of tumor blood flow was found after administration of epinephrine, norepinephrin and ethylphenylephrine. In addition, metaraminol and phenyleprine as well as 1. 0 and 2. 5mg/ ml methoxamine were not found to significantly change blood flow of the tumor.