Regulation of the renal transport of inorganic sulfate: effects of metabolic changes in arterial blood pH.

The present experiments were designed to examine the effects of mild metabolic changes of blood pH on the reabsorption of inorganic sulfate (SO4) in the rat. Female adult Sprague Dawley rats (which were kept on a standard diet) were used. In order to produce either a metabolic alkalosis (Alk) or a metabolic acidosis (Ac), 130 mmol/l NaHCO3 or a mixture of 130 mmol/l NH4Cl and 130 mmol/l NaCl was infused. The blood pH values were 7.49 +/- 0.02 and 7.29 +/- 0.02, respectively. The fractional excretion (FE) of SO4 was 28.6 +/- 5.7 (Alk) and 9.5 +/- 2.7 (Ac), respectively. These changes were significant (P less than 0.001). It is concluded, that physiological metabolic changes of blood pH may be important in the renal regulation of the transport of SO4.