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Vitamin D pp 91-123 | Cite as

Vitamin D Metabolism

  • Joseph L. Napoli
  • Ronald L. Horst

Abstract

The demonstration that l,25-(OH)2D3 is a hormone which governs calcium homeostasis has focused attention on the mechanisms of l,25-(OH)2D3 action, and the processes that regulate its production. Much less attention has been directed to the other metabolites of 25-OH-D3, and most of that has concerned 24R,25-(OH)2D3, a compound whose function is controversial. The complex metabolism of 25-OH-D3, other than 1α-hydroxylation, may be a degradative mechanism. It is equally conceivable that there are other functions of vitamin D, and that metabolites of 25-OH-D3 and l,25-(OH)2D3 support such functions in bone, kidney, intestine, and muscle. It is the purpose of this review to concentrate on developments in vitamin D metabolism that have occurred since 1978, which might affect appraisal of the importance of 25-OH-D3 metabolism, other than through 1α-hydroxylation. Advances in the methods used to study vitamin D metabolism, especially high performance liquid chromatography (HPLC) and mass spectroscopy, will be discussed. The reader is directed to a number of reviews for a broad view of vitamin D metabolism and action (1–7).

Keywords

High Performance Liquid Chromatography High Performance Liquid Chromatography System Kidney Homogenate Intestinal Calcium Transport Chick Kidney 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Martinus Nijhoff Publishing, Boston/The Hague/Dordrecht/Lancaster 1984

Authors and Affiliations

  • Joseph L. Napoli
  • Ronald L. Horst

There are no affiliations available

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