Promene unutarćelijske lokalizacije glukokortikoidnog receptora izazvane hipertermijskim stresom

Abstract

The aim of the present study was to examine intracellular redistribution of the glucocorticoid receptor (GR) in rat liver cells during a 24-h time period after exposure of the animals to 41°C whole body hyperthermic stress. The level of the receptor protein in the cytoplasmic and nuclear compartments was measured by immunoblotting procedures applied to both crude cytosol and immunopurified GR, as well as by immunocytochemical analyses applied to both paraffin-embedded liver sections and unfixed nuclear smears. All the experimental approaches employed in the study provided similar results, demonstrating that the transient stress-related decline of the cytoplasmic GR observed during the first five hours after exposure of the animals to whole-body hyperthermic stress is accompanied by enhanced nuclear accumulation of the receptor. The study can contribute to a better understanding of the influence of stress on the glucocorticoid signal transduction pathway.

Cilj ove studije bio je da se ispita unutarćelijska redistribucija glukokortikoidnog receptora (GR) u ćelijama jetre pacova tokom 24-časovnog vremenskog perioda posle izlaganja životinja hipertermijskom stresu od 41°C. Zastupljenost receptornog proteina u citoplazmatičnoj i jedarnoj frakciji određivana je tehnikom imunoblotinga primenjenom na ukupni citosol i na prečišćeni GR, kao i imunocitohemijskom analizom primenjenom na parafinske preseke i na razmaze nefiksiranih, izolovanih jedara. Svi eksperimentalni pristupi korišćeni u ovom radu dali su slične rezultate koji pokazuju da je prolazno smanjenje citoplazmatičnog GR, zapaženo tokom prvih 5 časova nakon izlaganja životinja hipertermijskom stresu, praćeno povećanom akumulacijom receptora u jedrima. Ova studija bi mogla da doprinese boljem razumevanju uticaja stresa na put prenosa glukokortikoidnog signala kroz ćeliju.