Influence of the vitamin D-binding protein on the serum concentration of 1,25-dihydroxyvitamin D3. Significance of the free 1,25-dihydroxyvitamin D3 concentration.

The influence of the serum binding protein (DBP) for vitamin D and its metabolites on the concentration of its main ligands, 25-hydroxyvitamin D(3) (25-OHD(3)) and 1,25-dihydroxyvitamin D(3) (1,25-[OH](2)D(3)) was studied. The concentration of both 1,25-(OH)(2)D(3) and DBP in normal female subjects (45+/-14 ng/liter and 333+/-58 mg/liter, mean+/-SD, respectively; n = 58) increased during the intake of estro-progestogens (69+/-27 ng/liter and 488+/-90 mg/liter, respectively; n = 29), whereas the 25-OHD(3) concentration remained unchanged. A positive correlation was found between the concentrations of 1,25-(OH)(2)D(3) and DBP in these women. At the end of pregnancy, the total concentrations of 1,25-(OH)(2)D(3) (97+/-26 ng/liter, n = 40) and DBP (616+/-84 mg/liter) are both significantly higher than in nonpregnant females and paired cord serum samples (48+/-11 ng/liter and 266+/-41 mg/liter, respectively). A marked seasonal variation of 25-OHD(3) was observed in pregnant females and their infants, whereas in the same samples the concentrations of both DBP and 1,25-(OH)(2)D(3) remained constant throughout the year. The free 1,25-(OH)(2)D(3) index, calculated as the molar ratio of this steroid and DBP, remains normal in women taking estro-progestogens, however, and this might explain their normal intestinal calcium absorption despite a high total 1,25-(OH)(2)D(3) concentration. In pregnancy the free 1,25-(OH)(2)D(3) index remains normal up to 35 wk of gestation, but during the last weeks of gestation, the free 1,25-(OH)(2)D(3) index increases in both circulations. A highly significant correlation exists between the (total and free) 25-OHD(3) and 1,25-(OH)(2)D(3) concentrations in maternal and cord serum both at 35 and 40 wk of gestation.

[1]  T. K. Gray,et al.  Radioimmunoassay for 1,25-dihydroxycholecalciferol. , 1980, Clinical chemistry.

[2]  H. DeLuca,et al.  1α-Hydroxy D 3 with and without oestrogen in the treatment of osteoporosis , 1981 .

[3]  P. D. de Moor,et al.  Comparative study of the affinity of the serum vitamin D-binding protein. , 1980, Journal of steroid biochemistry.

[4]  H. DeLuca,et al.  Vitamin D homeostasis in the perinatal period: 1,25-dihydroxyvitamin D in maternal, cord, and neonatal blood. , 1980, The New England journal of medicine.

[5]  D. Brown,et al.  Role of pituitary hormones in regulating renal vitamin D metabolism in man. , 1980, British medical journal.

[6]  R. Bouillon,et al.  THE TRANSPORT OF VITAMIN D , 1980, Pediatric Research.

[7]  H. DeLuca,et al.  In vitro production of 1,25-dihydroxyvitamin D3 by rat placental tissue. , 1979, Proceedings of the National Academy of Sciences of the United States of America.

[8]  B. Lund,et al.  Plasma 1,25-dihydroxyvitamin D levels in pregnancy and lactation. , 1979, Acta endocrinologica.

[9]  Y. Weisman,et al.  1α, 25-Dihydroxyvitamin D3, and 24,25-dihydroxyvitamin D3 in vitro synthesis by human decidua and placenta , 1979, Nature.

[10]  G. Braunstein,et al.  Changes in 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D during pregnancy. , 1979, American journal of obstetrics and gynecology.

[11]  A. Norman,et al.  Acromegaly and vitamin D metabolism: effect of bromocriptine treatment. , 1979, The Journal of clinical endocrinology and metabolism.

[12]  H. DeLuca,et al.  Intestinal calcium absorption and serum vitamin D metabolites in normal subjects and osteoporotic patients: effect of age and dietary calcium. , 1979, The Journal of clinical investigation.

[13]  H. DeLuca,et al.  Evidence that increased circulating 1 alpha, 25-dihydroxyvitamin D is the probable cause for abnormal calcium metabolism in sarcoidosis. , 1979, The Journal of clinical investigation.

[14]  H. Fleisch,et al.  Regulation of the metabolism of 25-hydroxyvitamin D3 in primary cultures of chick kidney cells. , 1979, The Journal of clinical investigation.

[15]  R. Lorenc,et al.  Evidence for extra-renal 1 alpha-hydroxylation of 25-hydroxyvitamin D3 in pregnancy. , 1979, Science.

[16]  D. Goodman,et al.  Quantitative studies of the interaction of cholecalciferol ((vitamin D3) and its metabolites with different genetic variants of the serum binding protein for these sterols. , 1979, The Biochemical journal.

[17]  R. Kumar,et al.  Elevated 1,25-dihydroxyvitamin D plasma levels in normal human pregnancy and lactation. , 1979, The Journal of clinical investigation.

[18]  S. Manolagas,et al.  Glucocorticoids regulate the concentration of 1,25-dihydroxycholecalciferol receptors in bone , 1979, Nature.

[19]  J. Lefaivre,et al.  Fetal blood calcium response to maternal hypercalcemia induced in the cow by calcium infusion or by solanum glaucophyllum ingestion. , 1979, Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme.

[20]  H. DeLuca,et al.  Synergistic effect of progesterone, testosterone, and estradiol in the stimulation of chick renal 25-hydroxyvitamin D3-1alpha-hydroxylase. , 1978, Endocrinology.

[21]  Y. Weisman,et al.  Synthesis of 1,25-dihydroxyvitamin D in the nephrectomized pregnant rat. , 1978, Endocrinology.

[22]  R. Recker,et al.  Menopausal changes in calcium balance performance. , 1978, The Journal of laboratory and clinical medicine.

[23]  R. Lorenc,et al.  Evidence for Maternal and Fetal Differences in Vitamin D Metabolism , 1978, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine.

[24]  J. Besnard,et al.  Correlation of free thyroxine index and thyroxine: thyroxine-binding globulin ratio with the free thyroxine concentration as measured by the thyroxine and thyroxine-binding globulin radioimmunoassays. , 1978, Clinica chimica acta; international journal of clinical chemistry.

[25]  K. T. Chong,et al.  Effect of oestrogen and 1,25-dihydroxycholecalciferol on 25-hydroxycholecalciferol metabolism in primary chick kidney-cell cultures. , 1978, The Biochemical journal.

[26]  P. D. de Moor,et al.  Immunochemical measurement of the vitamin D-binding protein in rat serum. , 1978, Endocrinology.

[27]  R. Recker,et al.  Effect of estrogens and calcium carbonate on bone loss in postmenopausal women. , 1977, Annals of internal medicine.

[28]  A. D. Kenny,et al.  Vitamim D3 metabolism in immature Japanese quail: effects of ovarian hormones. , 1977, Endocrinology.

[29]  P. D. de Moor,et al.  25-hydroxyvitamin D and its binding protein in maternal and cord serum. , 1977, The Journal of clinical endocrinology and metabolism.

[30]  P. D. de Moor,et al.  The measurement of the vitamin D-binding protein in human serum. , 1977, The Journal of clinical endocrinology and metabolism.

[31]  J. Lemann,et al.  The importance of phosphate in regulating plasma 1,25-(OH)2-vitamin D levels in humans: studies in healthy subjects in calcium-stone formers and in patients with primary hyperparathyroidism. , 1977, The Journal of clinical endocrinology and metabolism.

[32]  D. Goodman,et al.  Immunological and immunoassay studies of the binding protein for vitamin D and its metabolites in human serum. , 1977, The Journal of clinical investigation.

[33]  J. Haddad,et al.  Radioimmunoassay of the binding protein for vitamin D and its metabolites in human serum: concentrations in normal subjects and patients with disorders of mineral homeostasis. , 1976, The Journal of clinical investigation.

[34]  P. D. de Moor,et al.  Measurement of 25-hydroxyvitamin D3 in serum. , 1976, Clinical chemistry.

[35]  M. Haussler,et al.  THE ASSAY OF 1α, 25‐DIHYDROXYVITAMIN D3: PHYSIOLOGIC AND PATHOLOGIC MODULATION OF CIRCULATING HORMONE LEVELS , 1976, Clinical endocrinology.

[36]  C. Dent,et al.  PLASMA 25-HYDROXYVITAMIN-D LEVELS DURING PREGNANCY IN CAUCASIANS AND IN VEGETARIAN AND NON-VEGETARIAN ASIANS , 1975, The Lancet.

[37]  R. Rosenfield,et al.  Studies of the relation of plasma androgen levels to androgen action in women. , 1975, Journal of steroid biochemistry.

[38]  J. Felber,et al.  Free cortisol index: a rapid and simple estimation of free cortisol in human plasma. , 1975, The Journal of clinical endocrinology and metabolism.

[39]  S. Birge,et al.  Widespread, specific binding of 25-hydroxycholecalciferol in rat tissues. , 1975, The Journal of biological chemistry.

[40]  J. Haddad,et al.  Human perinatal vitamin D metabolism. I. 25-Hydroxyvitamin D in maternal and cord blood. , 1974, The Journal of pediatrics.

[41]  L. Finberg,et al.  25-Hydroxyvitamin D. Plasma levels in mothers and their premature infants with neonatal hypocalcemia. , 1974, American journal of diseases of children.

[42]  I. Chopra,et al.  Competitive ligand-binding assay for measurement of sex hormone-binding globulin (SHBG). , 1973, The Journal of clinical endocrinology and metabolism.

[43]  A. Horsman,et al.  The crush fracture syndrome in postmenopausal women. , 1973, Clinics in endocrinology and metabolism.

[44]  D. Barltrop,et al.  Absorption, Accretion and Endogenous Faecal Excretion of Calcium by the Newborn Infant , 1973, Nature.

[45]  P. D. de Moor,et al.  Pathophysiological data obtained with a radioimmunoassay for human parathyroid hormone. , 1973, Annales d'endocrinologie.

[46]  P. Kelly,et al.  Short- and long-term effects of estrogen and synthetic anabolic hormone in postmenopausal osteoporosis. , 1972, The Journal of clinical investigation.

[47]  J. Canterbury,et al.  Physiologic hyperparathyroidism in pregnancy. , 1972, The Journal of clinical endocrinology and metabolism.

[48]  R. Heaney,et al.  Calcium metabolism in normal human pregnancy. , 1971, The Journal of clinical endocrinology and metabolism.

[49]  R. Rosenfield,et al.  Plasma testosterone binding globulin and indexes of the concentration of unbound plasma androgens in normal and hirsute subjects. , 1971, The Journal of clinical endocrinology and metabolism.

[50]  L. Avioli,et al.  Placental transfer of vitamin D3 and 25-hydroxycholecalciferol in the rat. , 1971, The Journal of laboratory and clinical medicine.

[51]  L. Barness,et al.  Calcium and fat absorption in neonatal period. , 1970, The American journal of clinical nutrition.

[52]  I. Shenolikar.  Absorption of dietary calcium in pregnancy. , 1970, The American journal of clinical nutrition.

[53]  B. Nordin,et al.  SPINAL OSTEOPOROSIS AND THE MENOPAUSE. , 1965, Proceedings of the Royal Society of Medicine.

[54]  J. Hirschfeld,et al.  Serum Protein Synthesis in Fœtus Haptoglobins and Group-Specific Components , 1962, Nature.

[55]  P. D. de Moor,et al.  Protein binding of corticoids studied by gel filtration. , 1962, The Journal of clinical investigation.