Effects of phytic acid on renal stone formation in rats.

The effects of phytic acid and phytic acid/zinc mixtures on renal urolith development in an animal model of nephrolitiasis were studied. Male rats were divided into four groups of 15, 10, 10 and 12 rats each. The rats of Group I were treated with ethylene glycol; of Group II with ethylene glycol plus zinc; of Group III with ethylene glycol phytic acid; and of Group IV with ethylene glycol plus a mixture of phytic acid/zinc. Urine analysis (24 h) was carried out to determine the levels of calcium, oxalate, citrate, zinc and phytic acid in each group. At the end of the experiment all kidneys were removed and examined macroscopically and microscopically for possible crystal/stone locations and the total calcium amount in the renal papillary tissue was evaluated. In the rats treated with the aqueous phytic acid and phytic acid/zinc mixture, the number of calcifications on the papillary tips and the total calcium amount of the papillary tissue were significantly reduced compared with the controls treated exclusively with ethylene glycol or ethylene glycol plus zinc. Consequently, phytic acid and mixtures of phytic acid/zinc may be a useful agent in the treatment of patients with calcic urolithiasis.