ABSTRACT
By using ~3H—TdR incorporation and CTLL—2 cell line,we observed effects of RU486,anantagonist of type Ⅱ glucocorticoid receptor,on dexamethasone inhibition of lymphocyte prolifer-ation and interleukin—2(IL—2)production in rat spleen.It was shown that RU486 obviouslyantagonized the inhibitory actions of dexamethasone on lymphocyte proliferation and IL—2 pro-duction.By means of dot hybridization and Northern blot analysis,effects of dexamethasone andRU486 on IL—2 gene expression were investigated in lymphocytes of rat spleen.The datademonstrated that dexamethasone markedly decreased IL—2 mRNA production,RU486 alonedidn't affect IL-2 mRNA levels,but obviously reversed dexamethasone-mediated downregala-tion of IL—2 mRNA production in ConA—activated lymphocytes.These results suggest thatthe above effects of dexamethasone may be mediated by glucocorticoid receptor in lymphocytesof rat spleen.