No Difference in Intestinal Strontium Absorption After an Oral or an Intravenous 1,25(OH)2D3 bolus in Normal Subjects
- 1 October 1999
- journal article
- clinical trial
- Published by Oxford University Press (OUP) in Journal of Bone and Mineral Research
- Vol. 14 (10) , 1789-1795
- https://doi.org/10.1359/jbmr.1999.14.10.1789
Abstract
It has been suggested that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) stimulates intestinal calcium absorption less via the intravenous (iv) than the oral route, because the first avoids direct contact of the drug with the enterocytes. However, no study has addressed the issue directly. This investigation was designed to measure the effect of a single oral or iv dose of 1,25(OH)2D3 on calcium absorption, using stable strontium (Sr) as a surrogate for calcium, and measuring the Sr fractional absorbed dose (FAD%) over 240 minutes after Sr administration. In 10 healthy volunteers, five tests were performed in a cross-over design, with a wash-out period between two consecutive tests: Sr absorption without 1,25(OH)2D3 (test A); Sr absorption immediately after either oral (test B) or iv (test C) 1,25(OH)2D3 (1.5 μg/m2 of body surface area [BSA]); Sr absorption (24 hr after either oral (test D) or iv (test E) 1,25(OH)2D3 (1.5 μg/m2 BSA). The concurrent administration of 1,25(OH)2D3 and Sr (tests B and C) did not significantly change the area under the Sr FAD%–time curve with respect to test A (test A: 4090 ± 345; test B: 4510 ± 345; test C: 4210 ± 345), whereas Sr absorption was significantly increased (p < 0.001) when Sr was given 24 hr after either oral or iv 1,25(OH)2D3 (test D: 5710 ± 345; test E: 5510 ± 345). It was concluded that 1,25(OH)2D3 is likely to influence calcium absorption significantly only via its genomic effect, independent of its administration route.Keywords
This publication has 28 references indexed in Scilit:
- 1,25(OH)2-vitamin D3, a steroid hormone that produces biologic effects via both genomic and nongenomic pathwaysThe Journal of Steroid Biochemistry and Molecular Biology, 1992
- Metabolism of Ca and Sr in Late Adult LifeHealth Physics, 1990
- 1,25(OH)2 vitamin D3 stimulates membrane phosphoinositide turnover, activates protein kinase C, and increases cytosolic calcium in rat colonic epithelium.Journal of Clinical Investigation, 1990
- Intravenous Calcitriol in the Treatment of Refractory Osteitis Fibrosa of Chronic Renal FailureNew England Journal of Medicine, 1989
- 1,25(OH)2 vitamin D3 inhibits parathyroid cell proliferation in experimental uremiaKidney International, 1989
- Simple test of intestinal calcium absorption measured by stable strontium.BMJ, 1987
- Trans‐ and paracellular calcium transport across the colonic mucosa after short‐ and long‐term treatment with 1,25‐dihydroxyvitamin D3European Journal of Clinical Investigation, 1986
- Marked suppression of secondary hyperparathyroidism by intravenous administration of 1,25-dihydroxy-cholecalciferol in uremic patients.Journal of Clinical Investigation, 1984
- An analysis of variance test for normality (complete samples)Biometrika, 1965
- Active Transport of Calcium by Rat Duodenum in vivoScience, 1961