We have previously reported that in peripheral blood mononuclear cells (PBMC), the augmented expression of the P isoform of the human glucocorticoid receptor (hGRbeta), as a putative dominant negative regulator of glucocorticoid action, is associated with glucocorticoid (GC) unresponsiveness of UC patients. In this study, we quantified the levels and serial changes of hGR transcripts in PBMC of IBD patients by a real-time fluorescence monitoring of PCR. As results, relative hGRbeta mRNA expression was significantly higher in the active stage of UC than in inactive periods of UC or CD patients. Longitudinal analysis revealed that bGRbeta mRNA expression in UC was increased after the relapse of inflammation, suggesting that the overproduction of cytokines during inflammation may be responsible. In in vitro culture experiments of human lymphoid cell (CEM) and human PBMC, IL-7, and IL-18 increased hGRbeta mRNA expression in these cells but GC itself did not. Through these analyses, it is indicated that the inflammatory cytokines altered the splicing condition of the primary transcript of hGR gene in IBD patients. (C) 2002 Elsevier Science (USA). All rights reserved.