Science · 1974 · 192 citations · 16 references
MedicineEndocrinologyNutritional SciencesBone MetabolismCalcium HomeostasisMineral MetabolismCalcium MetabolismVitamin DVitamin D DeficiencyVitamin D MetabolismVitamin MetabolismVitamin PhysiologyDaily DosingNutritional Vitamin D StatusRenal Vitamin D MetabolismVitamin D InsufficiencyVitamin D Metabolism ImpairmentVitamin D MetabolitesVitamin D PhysiologyVitamin D Synthesis
Vitamin D-deficient rats produce [(3)H]1,25-dihydroxyvitamin D(3) from [(3)H]25-hydroxyvitamin D(3) regardless of dietary content of calcium or phosphate. A daily dose of 130 picomoles of 1,25-dihydroxyvitamin D(3) for a period of 5 days reduces production of [(3)H]1,25-dihydroxyvitamin D(3) to essentially zero and stimulates production of [(3)H]24,25-dihydroxyvitamin D(3). A daily dose of 325 picomoles of 25-hydroxyvitamin D(3) has a similar but less dramatic effect. On the other hand, 650 picomoles daily of 24,25-dihydroxyvitamin D(3) given to vitamin D-deficient rats had no effect. Thus it appears that 1,25-dihydroxyvitamin D(3) is an important factor in the regulation of kidney metabolism of 25-hydroxyvitamin D(3).
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Microdetermination of Phosphorus
P. S. Chen, T. Y. Toribara, Huber R. Warner · Analytical Chemistry · 1956 · 7.2K citations