The effects of protein restriction on body proteins and the liver in uraemic rats.

Controlled experiments have been undertaken to assess the effects of protein restriction on rats with experimentally induced chronic renal insufficiency Partially (five-sixths) nephrectomized weanling rats, taking a normal 16% protein diet, developed moderate uraemia. After 3 months, half were transferred to an isocaloric 8% protein diet and the plasma urea level fell to normal. Six months post-operatively, sham operated control rats on the low protein diet were not significantly different in weight, body proteins or liver pathology from those on normal diet. In contrast the partially nephrectomized rats on the low protein diet showed: (1) restricted growth, lower haemoglobin, plasma albumin and essential amino acid levels, (2) mild to severe fatty infiltration in all the livers and half with slight to severe necrosis and/or fibrosis (cirrhosis). Some fatty infiltration was also seen in the uraemic rats on the normal diet. The implications of these results are discussed with particular reference to the greater protein requirements in chronic renal insufficiency.