[Effects of urinary pH and acid-base balance on the formation of calcium oxalate stone].
The effects of urinary pH and acid-base balance on the calcium oxalate stone formation was investigated by two experiments. 24-hr urine samples were collected from 15 recurrent CaOx stone formers, 9 single stone formers and 6 age-matched controls. Inhibitory effect of 1% urine in various pH (4.0-9.0) were calculated by a seed crystal method. In the seed crystal system, there were no significant differences in the inhibitory activity of aggregation (Ia) and in the inhibitory activity of size (Is) for each pH of metastable solution between the stone former group and the control group. However, the value of Ia and Is showed a tendency of rise in proportion to a rise in pH. Rats model for calcium oxalate urolithiasis were fed with three different diets (1% NH4Cl, 5% NaHCO3 and 8% NaHCO3 diet) for three weeks. On the fourth week, 24-hr urine samples were collected. In the animal experiment, calcium oxalate stone formations were predominantly recognized in the kidney of the 1% NH4Cl diet group. The biochemical data showed an increase of urinary calcium and oxalate, and a decrease of urinary citrate. These results suggest that low urinary pH and metabolic acidosis are promoters of the calcium oxalate stone formation.
Iida
S
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Department of Urology, Kurume University School of Medicine.
D000136:Acid-Base Equilibrium; D000138:Acidosis / Q000150:complications*; D000818:Animals; D002129:Calcium Oxalate / Q000032:analysis* / Q000378:metabolism; D004195:Disease Models, Animal; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014545:Urinary Calculi / Q000737:chemistry / Q000378:metabolism*; D014556:Urine
D002129:Calcium Oxalate