Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glucocorticoid receptor binding was compared in liver cytosol preparations from spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats using homologous displacement of [3H]dexamethasone. At 5 degrees C, there was no difference in receptor binding affinity or concentration between strains for dexamethasone, corticosterone or aldosterone. At 37 degrees C, affinity for dexamethasone was lower than at 5 degrees C for both rat strains and decreased with time. However, at this higher temperature, binding affinity in the SHR preparation was consistently higher than in the WKY preparation. The WKY preparation had a higher receptor concentration. The rate of dissociation of the [3H]dexamethasone-receptor complex prepared at 5 degrees C and then incubated at 37 degrees C was rapid but not different between strains. A possible explanation of these results is that the relationship of the heat shock proteins to the receptor heterocomplex is different between strains. Evidence exists of a genetic difference in Hsp 70 between SHR and WKY rats, although its cosegregation with blood pressure has not been established.
Steroids 1995 Jan
PMID:Differences in temperature-sensitive receptor binding of glucocorticoids in spontaneously hypertensive and normotensive Wistar-Kyoto rats. 779 20

Glucocorticoid receptor (GR) concentrations and the ability of the GR to dimerize are factors which influence sensitivity to glucocorticoids. Upon glucocorticoid binding, the GR is actively transported into the nucleus, a crucial step in determining GR function. We examined the effects of GR concentration and the ability to dimerize on GR nuclear import, export and nuclear distribution using both live cell microscopy of GFP-tagged GR and immunofluorescence of untagged GR, with both wild type GR (GRwt) and dimerization deficient GR (GRdim). We found that the observed rate of GR nuclear import increases significantly at higher GR concentrations, at saturating concentrations of dexamethasone (10(-6) M) using GFP-tagged GR, while with untagged GR it is only discernable at sub-saturating ligand concentrations (10(-10)-10(-9) M). Loss of dimerization results in a slower observed rate of nuclear import (2.5- to 3.3-fold decrease for GFP-GRdim) as well as a decreased extent of GR nuclear localization (18-27% decrease for untagged GRdim). These results were linked to an increased rate of GR export at low GR concentrations (1.4- to 1.6-fold increase for untagged GR) and where GR dimerization is abrogated (1.5- to 1.7-fold increase for GFP-GRdim). Furthermore, GR dimerization was shown to be required for the appearance of discrete GC-dependent GR nuclear foci, the loss of which may explain the increased rate of GR export for the GRdim. The reduction in the observed rate of nuclear import and increased rate of nuclear export displayed at low GR concentrations and by the GRdim could explain the lowered glucocorticoid response under these conditions.
Steroids 2013 Feb
PMID:Glucocorticoid receptor concentration and the ability to dimerize influence nuclear translocation and distribution. 2317 79