[Stress due to immobilization and low protein intake in rats. Biochemical changes].

Rats fed a control casein diet, when exposed to immobilization, loose more nitrogen, urea and vitamin C in urine. Animals receiving a protein deficient diet excrete less nitrogen, urea and ascorbic acid in urine than their controls. When protein deficiency and immobilization are associated, there is not an increase on the urinary excretion of those substance compared to the deficient animals.