期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1974
卷号:71
期号:4
页码:1431-1435
DOI:10.1073/pnas.71.4.1431
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:In vivo, a spirolactone (SC-26304) inhibited the effects of aldosterone on urinary K+:Na+ ratios and the binding of [3H]aldosterone to renal cytoplasmic and nuclear receptors. Cytoplasmic binding of [3H]aldosterone and [3H]spirolactone (SC-26304) was similar in magnitude and involved the same set of sites. Under three sets of conditions--(i) in the intact rat, (ii) in kidney slices, and (iii) in reconstitution studies (mixing prelabeled cytoplasm with either purified renal nuclei or chromatin), [3H]spirolactone (SC-26304) did not yield specific nuclear complexes in contrast to the reproducible generation of these complexes with [3H]aldosterone. In glycerol density gradients, cytoplasmic [3H]aldosterone receptor complexes sedimented at 8.5 S and 4 S in low concentrations of salt and at 4.5 S in high concentrations of salt. Cytoplasmic [3H]spirolactone (SC-26304) receptor complexes sedimented at 3 S in low concentrations of salt and 4 S in high concentrations of salt. These results are discussed in terms of an allosteric model of the receptor system.