a group of active metabolites of cholecalciferol (vitamin D3), numbered according to the carbon atom(s) on which a hydroxyl group is substituted. 1,25-Dihydroxycholecalciferol (calcitriol) is the most active derivative; it increases intestinal absorption of calcium and phosphate, enhances bone resorption, and prevents rickets, and, because of these activities at sites distant from the site of its synthesis, is considered to be a hormone.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
One of the vitamin D analogs and metabolites that influence the body's absorption and use of calcium and phosphorus. Vitamin D and its analogs prevent and are used to treat rickets, osteodystrophy, hypocalcemia, and hypophosphatemia.
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