Abstract:
:Rats were raised after weaning on a vitamin D-deficient diet which used whole wheat and casein as the major protein source. For at least the first year of life, plasma calcium concentrations of these rats were the same as those of vitamin D-replete rats, and the rate of growth was normal for at least 6 months. The following evidence establishes the vitamin D deficiency of the rats (both male and female) on this diet: (i) plasma levels of 1,25-dihydroxycholecalciferol (1,25-dihydroxyvitamin D3) became undetectable after 6 weeks on the diet; (ii) by 4 months of age, the epiphyseal growth plates of the tibia were significantly enlarged and disorganized; (iii) when subjected to fracture in a dynamic torsion machine, the femur showed marked weakening as indicated by stress analysis; (iv) isolated kidney cells from the deficient rats showed a 3-fold increase in 25-hydroxyvitamin D 1-hydroxylase activity. When mother rats were placed on the vitamin D-deficient diet during lactation, plasma calcium values in the pups decreased and remained low throughout life and there was a stunted body growth pattern. It is concluded that hypocalcemia is not a necessary manifestation of vitamin D deficiency, that the onset of vitamin D deficiency during neonatal life influences the calcium homeostatic system, and that the normocalcemic, vitamin D-deficient animal provides an experimental model in which the effects of vitamin D deficiency can be studied independently of hypocalcemia.
journal_name
Proc Natl Acad Sci U S Aauthors
Lester GE,VanderWiel CJ,Gray TK,Talmage RVdoi
10.1073/pnas.79.15.4791subject
Has Abstractpub_date
1982-08-01 00:00:00pages
4791-4issue
15eissn
0027-8424issn
1091-6490journal_volume
79pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-01-29 00:00:00