Representative images illustrating Nissl staining in coronal sections containing the mPFC (A-H) and NeuN immunoreactivity (I-L) from sham- (A,B,E,F,I,J) and brain-injured rats (C,D,G,H,K,L) that received sesame oil (Veh; A,C,E,G,I,K) or progesterone (Prog; B,D,F,H,J,L), at 4 weeks after sham- or brain-injury. Boxed area in panel A represents the prelimbic region of medial PFC depicted at higher magnification in panels E-L. Scale bar in panel D = 200 μm for panels A-D and in panel L = 50 μm for panels E-L.