Severity of chronic metabolic acidosis and growth of rats with chronic uremia.

To determine what levels of chronic metabolic acidosis affect growth in uremia, we compared two groups of uremic rats receiving a 30% protein diet. This diet induced acidosis in A rats (n = 52; pH: 6.9-7.35) which was prevented by the addition of NaHCO3 in the diet of B rats (n = 52; pH: 7.38-7.46). A rats were separated into five groups by increasing severity of acidosis and were matched with B rats of similar renal function. Comparison between A and B rats showed: (1) no difference in food intake; (2) a reduction of weight gain only for severe acidosis with pH around 7.20 or less; (3) a reduction of length gain which was observed for less severe acidosis than reduction of weight gain, but which did not exist for marginal acidosis (pH > 7.25).