[Concentration of urea in blood and organs during muscular activity].

Muscular activity increases the content of urea in blood, liver, and muscles equally. The urea content in the kidney, however, either decreases or does not change at all, increasing only after an exhausting work or during the rest. The amount of protein in the diet influences upon the urea quantity in the organism, but the level of it's change under the action of muscular activity remains practically identical in the regime of the different protein nutrition. The activity of arginase in the liver and muscles is equally changed with the changes of the urea content in the blood and tissues.