期刊名称:Journal of Nutritional Science and Vitaminology
印刷版ISSN:0301-4800
电子版ISSN:1881-7742
出版年度:1989
卷号:35
期号:5
页码:529-533
DOI:10.3177/jnsv.35.529
出版社:Center for Academic Publications Japan
摘要:Protein binding properties of 22-oxa-lα, 25-dihydroxyvitamin D3(22-oxa-1, 25-D3), a synthetic analogue of 1α, 25-dihydroxyvitamin D3(1, 25-D3), were compared with those of vitamin D3derivatives. The order of binding affinity to the chick embryonic intestinal receptor was 1, 25-D3>22-oxa-1, 25-D3>25-hydroxyvitamin D3(25-D3) >24R, 25-dihydroxyvitamin D3(24, 25-D3) >vitamin D3(D3), while that to the rat plasma vitamin D-binding protein (DBP) was 25-D3>24, 25-D3>D3>1, 25-D3>22-oxa-1, 25-D3. The binding potencies of 22-oxa-1, 25-D3to the receptor and DBP were about 1/8 and 1/600 of the respective values of 1, 25-D3. When the distribution of the tritiated compounds in human plasma components was examined by an in vitro polyacrylamide gel electrophoretic method, [3H]-22-oxa-1, 25-D3was found to bind only to the lipoproteins including chyromicron. These results suggest that the replacement of a carbon atom into an oxygen atom in the side chain structure of 1, 25-D3results significant decrease in the binding affinity to DBP and that 22-oxa-1, 25-D3is transported as a complex-form not with DBP but with lipoprotein to the target tissues.