CRHR2 and post-traumatic stress disorder: Therefore, in our experimental model of PTSD, we decided to investigate whether the intranasal administration of CRHR2 agonists could prevent the development of not only behavioral changes, but also changes in the gene expressions of different components of the CRH system, i.e., CRH, CRHR1, and CRHR2 in the BNST, PVN, and Amy.