[3-Methylhistidine as a parameter for the determination of muscle proteolysis in the post-stress syndrome and in diabetes mellitus].

The renal excretion of 3-methylhistidine was measured in healthy human volunteers under different diets. The excretion of 3-methylhistidine and total nitrogen was increased in 8 surgical patients. These findings are referred to an increased proteolysis mainly in the skeletal muscle. In four insulin-dependent diabetic patients (IDDM) the excretion of 3-methylhistidine into urine was increased only when referred to body weight. The interpretation of the 3-methylhistidine/creatinin ratio is discussed. In diabetic patients the total nitrogen excretion seems to be a better parameter for protein turnover than 3-methylhistidine. The data suggest that 3-methylhistidine excretion into urine is a suitable parameter for the determination of muscle protein turnover.