The influence of experimental diabetes on the serum and urinary glycopeptide compounds in rats.

In alloxan-diabetic rats the protein level in the secomucoid and the levels of neutral sugars and peptides in the serum and urinary non-diffusible sugar-peptide (serum and urinary NSP) fractions increased. The proportion of neutral sugars in seromucoid and serum NSP fraction decreased, while in the urinary NSP fraction this ratio increased. In streptozotocin-diabetic rats the ratio of neutral sugars to the peptides did not change in either fraction, while the ratio of these sugars to the total nitrogen in the serum and urinary NSP fractions increased. The total level of seromucoid as well as the levels of neutral sugars in the serum and urinary NSP fraction were raised in these rats. The comparison of the results with those obtained previously by Sarnecka-Keller et al. (1968, 1972, 1972 a) in natural diabetes showed that the alloxan-diabetic model is more suitable for the study of glycopeptide compound metabolism in this disease.