Influence of 31-Mev X-Rays on Excretion of Nitrogen Compounds in Isolated Liver of Irradiated Frogs

Abstract

Numerous authors have studied the changes brought about in the liver by wholebody irradiation with ionizing rays. Pohle and Bunting (1), Rhoades (2), and others hold that the liver is morphologically relatively resistant. Patt and Brues (3) are of the opinion that this resistance is partly due to the remarkable regenerative capacity of the liver. Rhoades (2) considers the changes in the liver parenchyma caused by irradiation as the secondary effect of an over-all intoxication. Experiments carried out in this laboratory do not support this view. The effect of ionizing rays on the functional ability of the liver is controversial. Schwartz et al. (4) established that the change of serum proteins irradiated with ionizing rays is not due to fundamental changes in the liver functions. Sherman and Forssberg (5), on the contrary, are of the opinion that the liver is radiosensitive. Gabrieli and Cuttler (6) likewise hold that the Kupfer cells are extremely sensitive to ionizing rays. The aim of this study was to determine, by means of the perfusion of frog liver, the level of nitrogen compounds excreted by Rana esculenta irradiated with X-rays. These experiments afford an opportunity of indirectly studying the effect of irradiation on the liver and on the protein metabolism therein. Gustafson and Koletsky (7) have established an increased nitrogen excretion through the kidneys of the irradiated animals. In this process the liver might play an important role. Williams et al. (8), Krise et al. (9), Kay et al. (10), Jackson and Entenman (11), and Hunter (12) have also established an increased excretion of nitrogen compounds through the urine after irradiation. Further it was found (13-18) that the activity of some enzymes in the liver is not, or is only slightly, changed. The experiments discussed below refer to the increased excretion of nitrogen compounds by isolated liver.