Figure 2. Changes in blood corticosterone concentration throughout drug administration and CCI periods.

Despite CCI surgery, daily administration of the GR agonist dexamethasone (DEX) led to a slight decrease of plasma corticosterone levels, persisting throughout the experiment. Injections of the GR antagonist RU-486 (RU) or vehicle (CON) per se had no effect on the concentration of circulating corticosterone. The chronic constriction injury (CCI) however triggered a persistent increase in plasma corticosterone levels. Data are presented as mean ± s.e.m. *p<0.05, **p<0.01 indicate significant differences between DEX and RU and ^#p<0.05, ^##p<0.01 between DEX and CON.