Expression of glucocorticoid receptors alpha and beta in mononuclear cells of peripheral blood in patients with glucocorticoid-induced ocular hypertension

Abstract

To study the expression of glucocorticoid receptors (alpha and beta) in mononuclear cells of peripheral blood (PBMCs) in patients with glucocorticoid-induced ocular hypertension (GIOH) and the relationship between of the expression of GRalpha and GRbeta in PBMCs and its susceptibility to GIOH. Case control study. Thirty-two patients with anaphylactic conjunctivitis were enrolled in this study. All of whom were received topical application of 0.1% dexamethasone. The patients with the elevation of intraocular pressure (IOP) over 8 mm Hg(1 mm Hg = 0.133 kPa) or higher within two weeks were defined as GIOH and the others were considered as control group. There were no statistical difference in sex, average age, and baseline IOP between two groups. Each group consisted of sixteen patients. GRalpha and GRbeta mRNA (relative value) in PBMCs were detected with semi-quantitative reverse transcriptional polymerase chain reaction (RT-PCR), GRalpha and GRbeta protein (positive ratio) in PBMCs examined with fluorescent labelling flow cytometry. The GRalpha mRNA/GAPDH ratio of GIOH group was significantly (t = 3.872, P < 0.05) higher than that of control group (1.152 +/- 0.057 vs 1.048 +/- 0.031). The GRbeta mRNA/GAPDH of GIOH group was lower than that of control group's (1.055 +/- 0.034 vs 1.063 +/- 0.035), but was not statistically different (t = 0.419, P > 0.05). GRalpha positive percentage was significantly (t = 8.513, P < 0.01) higher in PBMCs of GIOH group than that of the control group (93.10 +/- 7.35)% vs (46.00 +/- 13.11)%, whereas GRbeta positive percentage was significantly (t = 4.842 P < 0.01) lower in PBMCs of GIOH group than that in control group (12.50 +/- 4.18)% vs (23.83 +/- 3.92)%. The higher expression of GRalpha in PBMCs in patients may have an implication of susceptibility to GIOH and warrant further investigation.