title: Effect of low calcium and low phosphorus diets on duodenal and ileal absorption of phosphate in chick.
abstract: The duodenal and ileal absorption of 32P was studied by an in vivo method in control chicks and in chicks fed for 2 weeks a diet deficient in calcium or phosphorus. The results showed a highly significant increase in duodenal and ileal phosphate absorption in chicks fed a low calcium diet and a smaller, though also significant increase in duodenal but not ileal phosphate absorption in chicks fed a low phosphorus diet. The adaptation phenomenon concerning intestinal phosphorus absorption is presumably due in part to a compensatory increase in 1,25-dihydroxy-vitamin D3 in both deficient diets. However, much higher renal l-hydroxylase activity was found in chicks fed the low calcium diet than in chicks fed the low phosphorus diet. The results indicate that duodenal and ileal absorption of phosphate is a vitamin D mediated process, but the adaptation to a low phosphorus diet tends to be less efficient than that to a low calcium diet, especially in the ileum.
mesh_terms: D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000008:administration & dosage / Q000172:deficiency*; D002645:Chickens; D004032:Diet; D004386:Duodenum / Q000378:metabolism; D007082:Ileum / Q000378:metabolism; D007408:Intestinal Absorption; D007668:Kidney / Q000201:enzymology; D008297:Male; D010710:Phosphates / Q000378:metabolism*; D010758:Phosphorus / Q000008:administration & dosage / Q000172:deficiency*; D013250:Steroid Hydroxylases / Q000378:metabolism*; D014807:Vitamin D / Q000502:physiology
chemical_list: D010710:Phosphates; D014807:Vitamin D; D010758:Phosphorus; D013250:Steroid Hydroxylases; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase; D002118:Calcium