Kenneth G. Scott

Distribution and Excretion of Electrolytes after Acute Whole-Body Irradiation Injury. II. Studies with Radiosodium.

Summary Rats show a substantial loss of potassium from a majority of radiosensitive tissues beginning within 24 to 48 hours after irradiation. There is a comparable loss of radiopotassium from bone. Radiopotassium excretion is increased in the urine of irradiated rats, and there is a rise in fecal levels with the onset of diarrhea. It is evident that rats that have been irradiated at over an LD50 level develop an absolute potassium deficiency.

Effect of Calcium Salt of Versene upon Metabolism of Plutonium in the Rat.

Conclusion 1. Oral administration of Versene in the rat at a toxic range did not produce a marked depletion of plutonium in soft tissues and had but little effect upon skeletal content. 2. When given parenterally large amounts of Versene depleted the skeletal content to a significant degree. 3. Under these conditions the absorption of plutonium from the intramuscular site of injection was increased. 4. These experiments indicate that it would appear that the use of Versene in chronic human plutonium poisoning offers little promise. 5. The prompt administration of Versene in large amounts might conceivably be of benefit when plutonium has entered the body by cuts or abrasions.

Retention of Orally Administered Radio-Phosphorus by Mice.∗

Summary Glucose increased and iron salts decreased the absorption of radioactive phosphorus from the gastro-intestinal tract.

Increased uptake of iodine-131 by the thyroid gland after administration of hesperidine methyl chalcone.

Scott(1) has shown that the rats thyroid takes up 50 to 200% more radioiodine under the influence of hesperidine methyl chalcone (H.M.C.). It was therefore decided to try this drug in human beings in order to determine its effect upon thyroidal accumulation of radioiodine. This drug is known to suppress the output of I131 through the kidney; probably I131 stays in the body in circulation a long enough time to favor increased uptake by the gland. Method. Nineteen patients having the diagnoses shown in Table I were studied. All of these were considered to be euthyroid except K.E. and O.C. who were judged to be hyper-and hypothyroid respectively . Two periods of tests were done on each patient. These were the first or the patients control period before the administration of H.M.C. and the second or his testing period following the administration of H.M.C. At the start of the control period, 20 μc I131 was given orally. Thyroid gland uptake measurements were done at 24-hour intervals for 96 hours. After a rest period of three days, the same patients thyroid uptake was again measured for residual I131 then 1.0 g of H.M.C. mixture in water was ingested. After an hour lapse to allow for effective absorption of the drug the patient ingested 80 μc I131. At 24-hour intervals, for 96 hours, his thyroid gland uptake was measured and due correction for decay and effective half-life was made for the residual I131 uptake from the control period. The tracer dose of 80 μ I131 was large enough to be readily measurable in the presence of residual I131 and thus also to minimize statistical differences between the measurements of the two periods. Results. Studies on the nineteen patients summarized in Table I show that the oral administration of one gram of H.M.C. significantly increases the thyroidal accumulation of I131.

Effect of Butazolidin upon the Fate of I131 in the Rat

During the course of the evaluation of other drugs upon the thyroidal accumulation of iodine in patients, it was observed that a patient being given butazolidinR had a very low I131 thyroid uptake. In this study rats were used in order to measure more completely the effect of this drug upon iodine metabolism. Methods. Young albino rats were given butazolidineR by subcutaneous injection at dosage levels ranging from 8 to 200 mg/kg body weight. In some groups of animals this was followed immediately by a tracer dose of 5 μc of I131 intraperitoneally. No additional iodide was added in these studies; thus the administration of the I131 served only to label the iodide pool of the body. The total amount of iodide present in 5 μc of I131 is calculated to be less than 1 × 10-3 μg. As will be noted in Table I, the uptake of I13 by control animals varied as much as 100%. Although the experimental and control animals for each group are of the same lot and origin, both Sprague Dawley and Slonaker strains of rats were employed in the several experiments combined in Table I. In our hands, Sprague Dawley rats recently received from Wisconsin have much higher thyroid uptake of I131 than that observed in rats bred locally. We believe that this merely represents a smaller iodide pool in rats imported from the Midwest since this higher uptake is reduced to that seen in local rats after a period of several weeks in their new environment. These animals were sacrificed 20 hours following I131 administration. Other groups of rats were given the drug daily for periods of 10 to 16 days in which the last injection of the drug was followed by 5 μc of I131.

Effect of Radio-Phosphorus on Blood of Monkeys.

Conclusions 1. Radiophosphorus lowers the absolute numbers of red cells, lymphocytes, and granulocytes in monkeys. 2. The degree of effect is about the same in lymphocytes and granulocytes, red cells being less affected. 3. Monkeys tolerated dosages of .76 and .71 millicuries of radiophosphorus per pound of body weight, 1.04 millicuries per pound being fatal. 4. The tolerance levels of radiophosphorus are about 10 times that usually used therapeutically.

The Distribution of Radioisotopes of Some Heavy Metals in the Hat

A summary is presented of data on the biological half times amd the principal deposition sites of 18 heavy metals in rats. Tracer techniques were used in the studies. Data are included on the following elements: Cd, Hg, In, Tl, M, Pb, Nb, Ta, Mo, W, Tc, Re Ru, Os, Rh, Ir, Pd, and Pt. (C.H.)