CRH and Anxiety: Nicotine withdrawal produces increases in extracellular CRF levels in the CeA, and antagonism of the CRF receptors has been shown to block anxiety-like behavior and deficit in brain reward function seen with precipitated nicotine withdrawal in rodents (George et al. 2007; Bruijnzeel et al. 2007; Heinrichs 2003; Heinrichs and Koob 2004).