Altered functioning of the HPA axis likely drove the heightened sensitivity to acute stressors and anxiety-provoking situations in NMS rats (Taché et al., 2001; O’Malley et al., 2011a), as CRF mRNA and CRF1 immunoreactivity were both elevated following NMS in PVN, amygdala, and locus coeruleus (Plotsky et al., 2005). This evidence concerns the gene CRHR1 and Anxiety.