Effects of dexamethasone (Dex) administration on serum CORT, IL-6 levels and hemocytes in rats. (A) Dex administration lowers serum CORT level. Lowered CORT level is caused by the feedback inhibition of the HPA axis response to long-term Dex exposure; (B) Long-term Dex exposure reduces serum IL-6 level; (C) Dex administration decreases blood WBC counts; (D) Long-term Dex exposure declines Lymph counts. Definitions: CORT, corticosterone; IL-6, interleukin-6; WBC, white blood cell; Lymph, lymphocyte. Values are expressed as Mean ± SEM, n = 10, different from control, * p < 0.05 and ** p < 0.01.