Effects of total parenteral nutrition in rats with experimental chronic renal failure.

The effects of total parenteral nutrition (TPN) in partially nephrectomized rats (n = 17) and sham-operated controls (n = 12) were evaluated and compared to the effect of low and high nitrogen oral diets (6% and 24% protein). TPN included fat (9 g/kg per day), high energy (1385 KJ/kg per day), and low nitrogen content (0.6 g N/kg per day, corresponding to 8% protein) either as essential amino acids (EAA) or as a mixture of essential and nonessential amino acids (CAA). The parenteral nutrition was administered intravenously via a permanent catheter continuously for 10 days. Most animals tolerated the treatment with no signs of overhydration or electrolyte imbalances. Uremic rats on TPN gained in weight similarly to control animals, whereas uremic rats given oral diets showed a lower weight increase. Both amino acid solutions promoted positive nitrogen balance and growth. Plasma urea dropped during TPN and low protein oral feeding in uremic and control rats, but not in the high protein-fed animals. Serum creatinine decreased with TPN but not with oral feeding in uremic rats. Albumin and hemoglobin levels were significantly reduced in all uremic rats irrespective of dietary treatment. The experimental model presented here could be useful for further studies on parenteral nutrition in uremia.