Effect of metabolic acidosis in intestinal absorption of calcium and phosphorus.
To investigate the effect of metabolic acidosis on intestinal calcium (Ca) and phosphorus (P) absorption and vitamin D metabolism, metabolic balance studies and in vitro gut sac uptake of 45Ca and [32P]phosphate were performed in rats maintained on low-Ca and moderately low-P diet and fed NH4Cl for 3 or 9 days and pair-fed controls. Plasma 1,25(OH)2D concentration was measured in the rats fed NH4Cl for 9 days and their controls. Net Ca and P absorption was 87-92% in the acidotic rats and did not differ from control. Moreover, gut sac uptakes of 45Ca and [32P]phosphate were not different from control. Plasma 1,25(OH)2D was higher in the ammonium chloride-fed rats than in controls (213 +/- 44 vs. 110 +/- 12 pg/ml), and serum P was lower in the acidotic animals (4.6 +/- 0.7 vs. 7.6 +/- 0.3 mg/dl). These data indicate that metabolic acidosis does not depress the augmented intestinal absorption of calcium and phosphorus noted during their dietary deprivation nor reduce the plasma level of 1,25(OH)2D.
D000136:Acid-Base Equilibrium; D000818:Animals; D002118:Calcium / Q000097:blood*; D004100:Dihydroxycholecalciferols / Q000097:blood; D007408:Intestinal Absorption; D008274:Magnesium / Q000097:blood; D008297:Male; D010758:Phosphorus / Q000097:blood*; D051381:Rats; D014807:Vitamin D / Q000502:physiology
D004100:Dihydroxycholecalciferols; D014807:Vitamin D; D010758:Phosphorus; D008274:Magnesium; D002118:Calcium