Abstract
An assay method was developed for the determination of high-affinity oestradiol receptors in uterine supernatant preparations. When only high-affinity sites are present in such preparations, or when they predominate, the analysis of the equilibrium between oestradiol and receptor sites based on the Scatchard (1949) plot may be used to determine the dissociation constant of the equilibrium and the molar concentration of the high-affinity sites. When both high-affinity and low-affinity sites are present the Scatchard plot is no longer linear and cannot be used directly to determine high-affinity sites. Determination of the reverse velocity constants of the reaction between high-affinity (k−1) and low-affinity (k−2) receptor sites and [3H]oestradiol has shown that these constants differ by at least one order of magnitude. Advantage has been taken of this difference to introduce an additional step into the assay procedure that eliminates oestradiol bound to low-affinity sites and permits the determination of high-affinity sites in different species and under a variety of physiological conditions.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Baulieu E. E., Raynaud J. P. A "proportion graph" method for measuring binding systems. Eur J Biochem. 1970 Apr;13(2):293–304. doi: 10.1111/j.1432-1033.1970.tb00931.x. [DOI] [PubMed] [Google Scholar]
- Jensen E. V., Suzuki T., Kawashima T., Stumpf W. E., Jungblut P. W., DeSombre E. R. A two-step mechanism for the interaction of estradiol with rat uterus. Proc Natl Acad Sci U S A. 1968 Feb;59(2):632–638. doi: 10.1073/pnas.59.2.632. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Korenman S. G. Radio-ligand binding assay of specific estrogens using a soluble uterine macromolecule. J Clin Endocrinol Metab. 1968 Jan;28(1):127–130. doi: 10.1210/jcem-28-1-127. [DOI] [PubMed] [Google Scholar]
- Murphy B. E. Some studies of the protein-binding of steroids and their application to the routine micro and ultramicro measurement of various steroids in body fluids by competitive protein-binding radioassay. J Clin Endocrinol Metab. 1967 Jul;27(7):973–990. doi: 10.1210/jcem-27-7-973. [DOI] [PubMed] [Google Scholar]
- Steggles A. W., King R. J. The use of protamine to study [6,7-3H] oestradiol-17-beta binding in rat uterus. Biochem J. 1970 Aug;118(5):695–701. doi: 10.1042/bj1180695. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Toft D., Shyamala G., Gorski J. A receptor molecule for estrogens: studies using a cell-free system. Proc Natl Acad Sci U S A. 1967 Jun;57(6):1740–1743. doi: 10.1073/pnas.57.6.1740. [DOI] [PMC free article] [PubMed] [Google Scholar]