Fig. 2.

Effect of dietary protein restriction on urine ammonia, pH, and titratable acid. Top: changes in urinary ammonia excretion. Dietary protein restriction induced a rapid and sustained decrease in urinary ammonia excretion; there were no significant time-dependent changes in ammonia excretion in mice fed control, 20%, protein diet. *P < 0.05 vs. 20% protein diet; n = 11/group. Middle: changes in urine pH. Dietary protein restriction resulted in a slow, but gradual, alkalinization of urine pH. There were no time-dependent changes in urine pH in response to control, 20%, protein diet. Changes in urinary ammonia excretion were significant on the 1st day of dietary protein restriction, whereas change in urinary pH were not significant until the 3rd day. *P < 0.05 vs. 20% protein diet; n = 11/group. Bottom: titratable acid excretion. Dietary protein restriction did not change titratable acid excretion significantly on the 1st day, but it did on the 2nd day of dietary protein restriction, and there was no further change on either day 3 or day 10. *P < 0.05 vs. Pre; n = 5/group.