OBJECTIVETo study the effect of chronic occupational stress on the glucocorticoid receptor (GR) and immune function.

METHODSA cross-sectional study was conducted in 112 railway station dispatchers. Perceived job stress was assessed by means of the Chinese version of the Job Content Questionnaire. The subjects were divided into high, medium and low strain groups according to the job strain score of the questionnaire. The number of GR, percentage of T lymphocyte subpopulations, concentrations of cortisol and interleukin 2 (IL-2) in blood were measured.

RESULTSThe concentrations of serum cortisol in high and medium strain groups [(295.43 +/- 79.06) and (274.34 +/- 70.08) ng/ml respectively] were higher than that in low strain group [(181.01 +/- 53.41) ng/ml, P < 0.05]. GR binding capacity in both groups (4,330.0 +/- 1,001.0, 3,971.6 +/- 966.8 specific binding/cell respectively) were smaller than that in low strain group (5,141.3 +/- 1,068.5 specific binding/cell, P < 0.05). The percentage of CD(3) T lymphocyte in high strain group was higher than that in low strain group [(50.21 +/- 10.30)% vs (56.87 +/- 15.36)%, P < 0.05], and CD(4) T lymphocyte in high and medium strain groups were significantly smaller than that in low strain group [(23.27 +/- 10.01)%, (27.06 +/- 7.47)% vs (33.31 +/- 7.77)%, P < 0.05]. In contrast, the percentage of CD(8) T lymphocytes in high and medium strain groups were significantly higher than that in low strain group [(28.16 +/- 6.47)%, (25.54 +/- 6.70)% vs (21.91 +/- 5.93)%, P < 0.05]. The levels of serum IL-2 in high and medium groups were smaller than that in low strain group [(0.77 +/- 0.05), (0.80 +/- 0.07) vs (1.05 +/- 0.12) ng/ml, P < 0.05]. Correlation analysis showed that serum cortisol level was negatively correlated with CD(8) percentage (r = -0.612, P < 0.01).

CONCLUSIONChronic occupational stress may induce rise of glucocorticoid, down-regulation of GR and inhibition on immune function.