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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1976-3-15
|
| pubmed:abstractText |
Vitamin D3 gives rise to at least one hormone in which the kidney is utilized as an endocrine system. This hormone arises from 25-OH-D3 which in turn is synthesized in the liver from vitamin D3. The production of this calcium and phosphorus mobilizing hormone, namely 1,25-(OH)2D3, is strongly regulated by the need for calcium and phosphorus. The regulation of its production can occur only after initial 1,25-(OH)2D3 is made and brings about the appearance of 25-OH-D3-24hydroxylase. The need for calcium brings about a stimulation of parathyroid hormone secretion. The parathyroid hormone suppresses the 24-hydroxylase and stimulates the 1-hydroxylase. Alternatively, the need for phosphorus directly stimulates the 1-hydroxylase and suppresses the 24-hydroxylase. The 24-hydroxylation appears to be the initial reaction leading to the inactivation and excretion of vitamin D whereas the 1-hydroxylation is the reaction bringing about the activation of the molecule to 1,25-(OH)2D3. The 1,25-(OH)2D3, the 25-OH-D3 and an analog of 1,25-(OH)2D3, namely 1alpha-OH-D3, are potentially extremely useful in the treatment of metabolic bone diseases such as renal osteodystrophy, hepatically related disorders of calcium and bone metabolism, hypoparathyroidism, and vitamin D dependency disease. The 1alpha-OH-D3 is effective by virtue of its conversion to 1,25-(OH)2D3. The 25-hydroxylation of both 1alpha-OH-D3 and vitamin D3 itself occurs predominantly in the liver. Finally, it is not entirely settled whether 1,25-(OH)2D3 is active directly in all of the functions of viramin D or whether it must be further converted metabolically. A new metabolic pathway for vitamin D has been discovered in which 1,25-(OH)2D3 loses its 26 and 27 carbons to carbon dioxide, producing an unknown metabolite. It is not certain whether this pathway represents degradation of the 1,25-(OH)2D3 or its further activation.
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
AIM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/25-Hydroxyvitamin D3...,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Cholecalciferol,
http://linkedlifedata.com/resource/pubmed/chemical/Dihydroxycholecalciferols,
http://linkedlifedata.com/resource/pubmed/chemical/Hydroxycholecalciferols,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphorus,
http://linkedlifedata.com/resource/pubmed/chemical/Steroid Hydroxylases,
http://linkedlifedata.com/resource/pubmed/chemical/Vitamin D
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jan
|
| pubmed:issn |
0022-2143
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
87
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
7-26
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:173767-25-Hydroxyvitamin D3 1-alpha-Hydroxylase,
pubmed-meshheading:173767-Animals,
pubmed-meshheading:173767-Bone Development,
pubmed-meshheading:173767-Calcium,
pubmed-meshheading:173767-Cholecalciferol,
pubmed-meshheading:173767-Dihydroxycholecalciferols,
pubmed-meshheading:173767-Humans,
pubmed-meshheading:173767-Hydroxycholecalciferols,
pubmed-meshheading:173767-Intestinal Mucosa,
pubmed-meshheading:173767-Kidney,
pubmed-meshheading:173767-Liver,
pubmed-meshheading:173767-Muscles,
pubmed-meshheading:173767-Parathyroid Glands,
pubmed-meshheading:173767-Phosphorus,
pubmed-meshheading:173767-Renal Osteodystrophy,
pubmed-meshheading:173767-Steroid Hydroxylases,
pubmed-meshheading:173767-Structure-Activity Relationship,
pubmed-meshheading:173767-Vitamin D,
pubmed-meshheading:173767-Vitamin D Deficiency
|
| pubmed:year |
1976
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| pubmed:articleTitle |
Recent advances in our understanding of the vitamin D endocrine system.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Review
|