Journal of Clinical Endocrinology & Metabolism Vol. 59, No. 6 1063-1069 doi:10.1210/jcem-59-6-1063 Copyright © 1984 by the Endocrine Society. Plasma Vitamin D Metabolite Concentrations in Chronic Renal Failure: Effect of Oral Administration of 25-Hydroxyvitamin D3*BERNARD P. HALLORAN, PHILLIP SCHAEFER, MEYER LIFSCHITZ, MARILYN LEVENS and RALPH S. GOLDSMITH
Department of Medicine, University of California and Veterans Administration Medical Center San Francisco, California, 94121 Address correspondence and requests for reprints to: Bernard Halloran, Veterans Administration Medical Center (11), 4150 Clement Street, San Francisco, California 94121. The circulating concentrations of 1,25-dihydroxyvitamin D and 24,25-dihydroxyvitamin D are abnormally low in patients with chronic renal failure (CRF). To determine the importance of substrate (25-hydroxyvitamin D) concentration in this phenomenon, five patients with end stage renal disease treated with hemodialysis were given 25-hydroxyvitamin D3 (25-OH-D3) orally for 4 weeks. The serum concentration of 25-OH-D3 increased from a mean (±SEM) of 26 ± 5 ng/ml immediately before therapy to a maximum of 108 ± 5 ng/ml 4 weeks after beginning administration of 25-OH-D3. The concentrations of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), 24,25-dihydroxyvitamin D3 (24,25(OH)2D3), and 25,26-dihydroxyvitamin D3 (25,26(OH)2D3) increased from 6.6 ± 0.8 pg/ml, 0.29 ± 0.10 ng/ml, and 0.36 ± 0.06 ng/ml, respectively, immediately before 25-OH-D3 administration to 21.7 ± 2.2 pg/ml, 0.48 ± 0.09 ng/ ml; and 0.78 ± 0.12 ng/ml, respectively, after 4 weeks of administration of 25-OH-D3. These results suggest that substrate availability may be an important determinant of the circulating concentrations of these metabolites in patients with CRF. It seems possible that the therapeutic effects of 25-OH-D3 administration to the CRF patient may be mediated through the normal actions of 1,25-dihydroxyvitamin D3, 24,25-dihydroxyvitamin D3, and perhaps other metabolites rather than through analog effects of 25-OH-D3.
* Supported in part by the Veterans Administration and Grant AM-27112 from the NIH. Received December 1, 1983. This article has been cited by other articles:
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