Institute for Medical Research and Occupational Health
Abstract
The effect of various amounts of phosphates and vitamin D in the diet on calcium and strontium absorption was studied in rats. The animals were kept on experimental diet for 6 days and during that period they received radioactive isotopes of calcium (45Ca) and strontium (85Sr) in drinking water. Skeletal retention of radioactive calcium and strontium was determined. Increased dietary phosphates (from 0.5 to 1.2% P) were found to cause a reduction in the retention of radioactive calcium and strontium after oral administration of isotopes. The effect of phosphates proved to be much stronger on strontium than on calcium absorption. This is in agreement with our earlier results. The effect of phosphates on calcium and strontium metabolism proved independent of the vitamin D content in the diet if this content ranged from 200 to 800 I. U. per 100 g of dry food.Istraživali smo djelovanje različitih količina fosfata i D vitamina u hrani štakora na apsorpciju stroncija i kalcija iz probavnog trakta. Štakori su 6 dana bili na određenom dijetnom režimu, i u to su vrijeme primali radioaktivne izotope kalcija i stroncija (45Ca i 85Sr) oralnim putem. Odredili smo retenciju radioaktivnog kalcija i stroncija u skeletu. Povišeni sadržaj fosfata u hrani (od 0.5 na 1.2% P) izaziva sniženje apsorpcije radioaktivnog kalcija i stroncija iz probavnog trakta. Fosfati djelu i u znatno jače na metabolizam stroncija negoli kalcija. Ti su nalazi u skladu s našim ranijim rezultatima. Spomenuti efekti fosfata na metabolizam kalcija i stroncija nezavisni su od količine D vitamina u hrani ukoliko ona raste od 200 do 800 i. j. na 100 g suhe hrane
