AIM: Glucocorticoid (GC) resistant ulcerative colitis (UC)remains a serious disease and is difficult to manage.Although the molecular basis of GC insensitivity is still unknown, GC receptors (GRα and GRβ) may play an important role in it. This study was aimed to investigate the relationship between the expression of GRα and GRβin colonic mucosal cells of patients with UC, the efficacy of GC therapy and the intensity of inflammation.METHODS: Twenty-five cases of UC were classified into:GC sensitive (n = 16) and GC resistant (n =9) cases.Patients consisted of mild (n = 6), moderate 8) and severe (n = 11) cases. GRα and GRβ expression in colonic mucosal specimens were investigated by immunohistochemistry, and compared between GC resistant and sensitive groups, and also among various degrees of inflammation.RESULTS: All cases were positive for GRα and GRβexpression. Both positive association between GRαexpression and the response of UC to GC and strong negative association between GRβ expression and the response of UC to GC were identified. There was no significant association between GRα/GRβ expression and the degree of inflammation of UC.CONCLUSION: These findings suggest that both GRα and GRβ may play an important role in the action of GC, and that GRβ functions as a dominant negative inhibitor of GRα. Expression of GRα and GRβ in colonic mucosal cells of patients with UC may serve as predictors of glucocorticoid response, but can not function as markers of inflammatory intensity.