REGULATION OF GLUCOCORTICOID RECEPTOR BY GLUCOCORTICOIDSs STUDY ON THE HUMAN HEPATOCELLULAR CARCINOMA CELL LINE (SMMC-7721) / 第二军医大学学报

ABSTRACT

The effects of dexamethasone(Dex)on the 3H-Dex specific binding were studied in the human heptatocellular carcinoma cell line(SMMC-7721) by using counting vial culture assay.Cells were cultivated in the counting vials, as th; grew well and the monolayer cells adhered to the wall of vials.The cells were cultivated in the mdium containing 10-3,10-7, and 10-6mol/L Dex for 6, 12, 24 and 48 h, and then the specific binding of 3H-Dex at 30nmol/L of the ligand was determined after elimination of the effect of the occupancy of GR.It was found that 3H-Dex specific binding was not changed within 6 h, but decreased to 70% at 12 h and maintained at this level from 12 to 48 h in the Dex pretreated cells.The specific binding was recovered approximately to the control level 24 h after removal of Dex.These results indicate that glucocorticoids may down-regulate glucocorticoid receptor in vitro.