A rat model of moderate uraemia is described in which uraemic animals attain normal food intake and weight gain. Despite the low levels of the induced uraemia, which has been well defined, changes in plasma amino acid concentrations associated with experimental uraemia still occur. It appears from this study that a reduction in food intake is not a major factor in the aetiology of the plasma amino acid changes seen in uraemia and that the model may prove useful in future studies of experimental chronic renal failure.