Ratio of pAMPK/AMPK. Representative Western blots of total AMPK and phosphorylated AMPK (pAMPK) in the hippocampus (upper panel). Bar graphs show that the ratio of pAMPK/AMPK is significantly decreased in the prefrontal cortex (A) and hippocampus (B) of mTBI rats assigned to control housing. Housing rats in EE after mTBI restored ratio of pAMPK/AMPK to normal levels. Notably, an overall increase in pAMPK/AMPK is evident in the sham animals housed in EE. *p < 0.05, **p < 0.01. Legend: 1 – mTBI control housing, 2 – mTBI EE housing, 3 – sham control housing, and 4 – sham EE housing.