Effect of potato on acid-base and mineral homeostasis in rats fed a high-sodium chloride diet.
Excessive dietary NaCl in association with a paucity of plant foods, major sources of K alkaline salts, is a common feature in Western eating habits which may lead to acid-base disorders and to Ca and Mg wasting. In this context, to evaluate the effects of potato, rich in potassium citrate, on acid-base homeostasis and mineral retention, Wistar rats were fed wheat starch (WS) or cooked potato (CP) diets with a low (0.5 %) or a high (2 %) NaCl content during 3 weeks. The replacement of WS by CP in the diets resulted in a significant urinary alkalinisation (pH from 5.5 to 7.3) parallel to a rise in citrate and K excretion. Urinary Ca and Mg elimination represented respectively 17 and 62 % of the daily absorbed mineral in rats fed the high-salt WS diet compared with 5 and 28 % in rats fed the high-salt CP diet. The total SCFA concentration in the caecum was 3-fold higher in rats fed the CP diets compared with rats fed the WS diets, and it led to a significant rise in Ca and Mg intestinal absorption (Ca from 39 to 56 %; Mg from 37 to 60 %). The present model of low-grade metabolic acidosis indicates that CP may be effective in alkalinising urine, enhancing citrate excretion and ameliorating Ca and Mg balance.
Narcy
Agnès
A
Unité des Maladies Métaboliques et Micronutriments, Institut National de la Recherche Agronomique, Centre de Clermont-Ferrand/Theix, 63 122 Saint-Genès Champanelle, France.
Robert
Laetitia
L
Mazur
Andrzej
A
Demigné
Christian
C
Rémésy
Christian
C
D000136:Acid-Base Equilibrium / Q000187:drug effects*; D000818:Animals; D002118:Calcium / Q000652:urine; D002432:Cecum / Q000378:metabolism; D004032:Diet; D004435:Eating; D006706:Homeostasis / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007408:Intestinal Absorption / Q000187:drug effects; D008274:Magnesium / Q000652:urine; D008297:Male; D008903:Minerals / Q000652:urine*; D011188:Potassium / Q000652:urine; D051381:Rats; D017208:Rats, Wistar; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage / Q000494:pharmacology*; D011198:Solanum tuberosum; D015430:Weight Gain
D008903:Minerals; D017673:Sodium Chloride, Dietary; D008274:Magnesium; D011188:Potassium; D002118:Calcium