Effects of Catecholamines on Cardiovascular Response and Blood Flow Distribution to Normal Tissue and Liver Tumors in Rats1

The effects of infusion of adrenaline and noradrenaline were studied in rats with intrahepatic tumors, using 99nTcand 51Crlabeled microspheres. The effect on general circulation, car diac output, and tissue blood flow was pronounced, especially with infusion of noradrenaline. Studies of liver tumor perfusion ¡nrelation to surrounding liver parenchyma perfusion showed an increased tumor/liver ratio in noradrenaline-infused rats, thus indicating a preferential blood flow to the tumors induced by this drug. Adrenaline as well as 0.9% NaCI solution infusion had no effect on tumor/liver blood flow ratios. Fluorescence microscopy and monoamine determination could not reveal any noradrenaline containing nerves in the liver tumors. These experiments might suggest that the effect of intraarterial infu sion with cytostatic agents might be enhanced by a simulta neously administered vasoconstrictor such as noradrenaline.