EFFECT OF MALNUTRITION ON PATTERN OF GROWTH IN RAT-KIDNEY AND RENAL RESPONSE TO ACIDOSIS

1. The kidneys of normal rats were analysed for water, fat, protein, RNA and DNA, at 10, 21 and 36 d after birth. The effects on growth caused by two types of malnutrition were investigated. 2. An increase in the RNA:DNA ratio was demonstrated between 10 and 36 d, contrary to previous evidence that this ratio is fixed at birth. 3. Energy deficiency during the first 21 d of life resulted mainly in fewer kidney cells, whereas protein-energy deficiency between 21 and 36 d resulted mainly in a smaller cellular content of RNA and protein. 4. In response to metabolic acidosis, both groups of malnourished rats increased urinary excretion of ammonia and there was enhanced gluconeogenesis in vitro; the basal rate of gluconeogenesis was lower in the protein-energy-deficient rats than in the controls. 5. Protein-energy-deficient rats did not exhibit the renal hypertrophy shown by the control rats in response to acidosis. © 1974, The Nutrition Society. All rights reserved.