NR3C1 and Anxiety: We examined GR and MR expression in the F0 hippocampus as both are key regulators of HPA-axis activity, besides being linked to anxiety phenotypes.15, 16, 17 CORT treatment reduced hippocampal GR mRNA levels (t(18)=2.793, P=0.012); however, there was no change in MR expression (t(18)=0.51697, P=0.6097; Figure 1g).