Excess casein in the diet is not the unique cause of low-grade metabolic acidosis: role of a deficit in potassium citrate in a rat model.
This study examined the effects of a dietary model of protein excess and K anion salt deficit on the occurrence of metabolic acidosis in rat. Rats were adapted to diets containing either 13 or 26% casein, together with mineral imbalance, through lowering K/increasing sodium/omitting alkalinizing anions. For each protein level, a group of rats was supplemented with K citrate. Dietary K citrate resulted in neutral urinary pH, whatever the protein level. Urea excretion was higher in rats adapted to 26% casein than 13% casein diets, but K citrate enhanced this excretion and suppressed ammonium elimination. No citraturia could be observed in acidotic rats, whereas K citrate greatly stimulated citraturia and 2-ketoglutarate excretion. In conclusion, low-grade metabolic acidosis can occur with a moderate protein level in the diet. K citrate was apparently less effective in rats adapted to the 26% casein level than in those adapted to the 13% casein level with regard to magnesium, citrate and 2-ketoglutarate concentrations in urine.
Sabboh
Houda
H
Unité des Maladies Métaboliques et Micronutriments, INRA de Clermont-Ferrand/Theix et CRNH d'Auvergne, St-Genès-Champanelle, France.
Besson
Catherine
C
Tressol
Jean-Claude
JC
Rémésy
Christian
C
Demigné
Christian
C
D000138:Acidosis / Q000209:etiology* / Q000378:metabolism* / Q000652:urine; D000818:Animals; D002364:Caseins / Q000008:administration & dosage* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects; D002149:Energy Intake / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008297:Male; D009584:Nitrogen / Q000378:metabolism*; D019357:Potassium Citrate / Q000008:administration & dosage* / Q000378:metabolism / Q000494:pharmacology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014508:Urea / Q000032:analysis / Q000493:pharmacokinetics; D016482:Urinalysis; D015430:Weight Gain / Q000187:drug effects
D002364:Caseins; D014508:Urea; D019357:Potassium Citrate; D009584:Nitrogen