Hyperthermic stress affects glucocorticoid receptor-mediated transcription in rat liver.
Binding capacity of the cytoplasmic and nuclear glucocorticoid receptor (GR) and the activity of tyrosine aminotransferase (TAT) were examined in the liver of intact and adrenalectomized rats exposed to 41 degrees C whole body hyperthermic stress. In glucocorticoid-deprived animals, stress-induced decrease in the cytoplasmic steroid binding was followed by parallel increases in its nuclear binding and TAT activity, suggesting a stimulation of TAT gene transcription by the GR in the absence of the ligand. In intact animals, however, a diminution of the steroid binding in the cytosol, its unchanged nuclear binding and an impairment of TAT activity were observed upon the stress. The results imply that stress could elicit different structural or functional alterations of unliganded vs liganded GR.
Vidović
S
S
School of Medicine, University of Banja Luka, Department of Biology and Human Genetics, Belgrade, Yugoslavia.
Cvoro
A
A
Dundjerski
J
J
Trajković
D
D
Matić
G
G
D000315:Adrenalectomy; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006979:Hyperthermia, Induced / Q000009:adverse effects*; D008099:Liver / Q000378:metabolism*; D008297:Male; D015735:Mifepristone / Q000494:pharmacology; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000502:physiology*; D013312:Stress, Physiological / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014444:Tyrosine Transaminase / Q000096:biosynthesis* / Q000235:genetics
D011965:Receptors, Glucocorticoid; D015735:Mifepristone; D014444:Tyrosine Transaminase