TY - JOUR
T1 - Effect of 1,25-dihydroxyvitamin D3 on calcium and magnesium absorption in the healthy human jejunum and ileum
AU - Krejs, Guenter J.
AU - Nicar, Michael J.
AU - Zerwekh, Joseph E.
AU - Norman, Daniel A.
AU - Kane, Mary G.
AU - Pak, Charles Y C
N1 - Funding Information:
From the Department of Internal Medicine, University of Texas Health Science Center at Dallas, Dallas, Texas. This work was supported in part by U.S. Public Health Service &ants P50-AM20543, MOlRR00633, and l-ROl-AM26390-01. Requests for reprints should be addressed to Dr. Cuenter J. Krejs, Department of internal Medicine, University of Texas Health Science Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75235.
PY - 1983/12
Y1 - 1983/12
N2 - In calcium deficiency states such as chronic renal failure, 1,25-dihydroxyvitamin D3 increases calcium and magnesium absorption toward normal levels. In the present study, the ability of exogenous 1,25-dihydroxyvitamin D3 to increase calcium and magnesium absorption above normal rates in healthy subjects was investigated. Steady-state perfusion studies were performed in 30 cm segments of jejunum and ileum before and after one week of 1,25-dihydroxyvitamin D3 administration (2 μg per day, 10 subjects). Serum 1,25-dihydroxyvitamin D concentration increased from 25.8 ± 2.5 pg/ml to 56.4 ± 6.6 (mean ± SEM, p < 0.05). In the basal state, calcium absorption was significantly higher in the jejunum than in the ileum. Vitamin D administration resulted in a significant increase in calcium absorption which was quantitatively similar in both the jejunum and ileum. The changes in net movement were due to an increase in lumen-to-plasma flux of calcium; the plasma-to-lumen flux remained unchanged. Jejunal magnesium absorption also was enhanced by 1,25-dihydroxyvitamin D3. These studies demonstrate that in healthy persons, exogenous 1,25-dihydroxyvitamin D3 increases calcium absorption in both the jejunum and the ileum, and increases magnesium absorption in the jejunum.
AB - In calcium deficiency states such as chronic renal failure, 1,25-dihydroxyvitamin D3 increases calcium and magnesium absorption toward normal levels. In the present study, the ability of exogenous 1,25-dihydroxyvitamin D3 to increase calcium and magnesium absorption above normal rates in healthy subjects was investigated. Steady-state perfusion studies were performed in 30 cm segments of jejunum and ileum before and after one week of 1,25-dihydroxyvitamin D3 administration (2 μg per day, 10 subjects). Serum 1,25-dihydroxyvitamin D concentration increased from 25.8 ± 2.5 pg/ml to 56.4 ± 6.6 (mean ± SEM, p < 0.05). In the basal state, calcium absorption was significantly higher in the jejunum than in the ileum. Vitamin D administration resulted in a significant increase in calcium absorption which was quantitatively similar in both the jejunum and ileum. The changes in net movement were due to an increase in lumen-to-plasma flux of calcium; the plasma-to-lumen flux remained unchanged. Jejunal magnesium absorption also was enhanced by 1,25-dihydroxyvitamin D3. These studies demonstrate that in healthy persons, exogenous 1,25-dihydroxyvitamin D3 increases calcium absorption in both the jejunum and the ileum, and increases magnesium absorption in the jejunum.
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U2 - 10.1016/0002-9343(83)90877-X
DO - 10.1016/0002-9343(83)90877-X
M3 - Article
C2 - 6689108
AN - SCOPUS:0021047580
SN - 0002-9343
VL - 75
SP - 973
EP - 976
JO - The American Journal of Medicine
JF - The American Journal of Medicine
IS - 6
ER -