The photoproduction of 1 alpha,25-dihydroxyvitamin D3 in skin: an approach to the therapy of vitamin-D-resistant syndromes
| Autor: | Sally Ann Holick, Michael F. Holick, John W. Henley, Julia A. MacLaughlin, John T. Potts, Milan R. Uskokovic |
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| Rok vydání: | 1980 |
| Předmět: |
Vitamin
Adult Male medicine.medical_specialty Calcitriol Photochemistry Ultraviolet Rays Metabolite Administration Topical Previtamin D3 chemistry.chemical_element Alpha (ethology) Calcium Ultraviolet therapy chemistry.chemical_compound Internal medicine medicine Animals Humans Intestinal Mucosa Vitamin D Cholecalciferol Skin Calcium metabolism business.industry Hydroxycholecalciferols General Medicine Syndrome Vitamin D Deficiency Rats Endocrinology Cholesterol chemistry Dihydroxycholecalciferols Female Ultraviolet Therapy business Skin Temperature medicine.drug |
| Zdroj: | The New England journal of medicine. 303(7) |
| ISSN: | 0028-4793 |
| Popis: | Cutaneous 7-dehydrocholesterol, exposed to ultraviolet radiation, converts to previtamin D3, which in turn converts in skin to vitamin D3 and is carried into the circulation. We investigated the feasibility of the photochemical conversion in skin of hydroxylated derivatives of 7-dehydrocholesterol - such as 1 alpha, 25-dihydroxy-7-dehydrocholesterol (1 alpha, 25-(OH)2-7-DHC) - to the corresponding hydroxylated previtamin as an alternative method of delivery of 1 alpha, 25-dihydroxyvitamin D3 (1 alpha, 25-(OH)2-D3) to subjects who are deficient in the endogenous metabolite. In human volunteers and in vitamin-D-deficient rats [24-3H] 1 alpha, 25-(OH)2-D3 appeared in blood after [24-3H] 1 alpha, 25-(OH)2-7-DHC was applied to the skin and exposed to ultraviolet radiation. In anephric rats, intestinal calcium absorption and serum calcium levels were elevated after a topical dose of 1 alpha, 25-(OH)2-7-DHC combined with ultraviolet phototherapy. Delivery of equivalent doses of 1 alpha, 25-(OH)2-D3 through the skin and orally showed that there was more prolonged stimulation in intestinal calcium absorption and serum calcium elevation after cutaneous administration. The photochemical conversion of precursors may be useful in the treatment of patients with impaired vitamin-D metabolism. |
| Databáze: | OpenAIRE |
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