Faculty Collaboration Database

Reversible inhibition of cytosolic glucocorticoid receptors by mercurial agents. Application in the measurement of total and unoccupied receptors. J Recept Res 1987;7(5):761-74

Date

01/01/1987

Pubmed ID

3656273

DOI

10.3109/10799898709056784

Scopus ID

2-s2.0-0023217529 (requires institutional sign-in at Scopus site)   1 Citation

Abstract

Recently developed "exchange assays" have been used to measure total cytosolic glucocorticoid receptor (GR) binding activity as compared to standard GR assays which measure unoccupied receptor. In the current study we modified these methods and extended the applications of such assays. Experiments defined the conditions whereby two sulfhydryl-binding agents, p-hydroxymercuribenzoate (PHMB) and mersalyl, completely inhibited binding of the glucocorticoid receptor to ligand in mouse renal cytosol. Reactivation of steroid-binding activity was restored by addition of dithiothreitol. The present study demonstrates 12% higher GR binding activity when this exchange assay is performed using saturated glucocorticoid-receptor complex, rather than standard cytosol. Combining the data from the standard and exchange mouse renal cytosolic GR assays, it was determined that, at physiologic tissue corticosterone levels, the respective mean concentrations of unoccupied, occupied, and total GR were 467, 89, and 556 fmol/mg cytosol protein. Measurement of receptor concentrations by the use of these methods permits precise experimental differentiation of factors which affect total, as well as unoccupied GR.

Author List

Ellis D, Tran SD, Eagon PK, Avner ED

Author

Ellis D. Avner MD Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Binding, Competitive
Cytosol
Dexamethasone
Dithiothreitol
Hydroxymercuribenzoates
Kidney
Kinetics
Mersalyl
Mice
Organomercury Compounds
Receptors, Glucocorticoid