Figure 1.

Schematic illustrating NE projections to the BNST in rat brain, and subsequent outputs from the BNST to other regions of the limbic system. In the case of opioid withdrawal, activation of NE neurons in the NTS and A1 cell groups enhance NE release in the BNST. NE acting at β-NE receptors in the BNST activates neurons projecting to various limbic regions, such as the nucleus accumbens (NAcc), amygdala, periaqueductal gray (PAG), hypothalamus, and perhaps other regions. Adapted from Aston-Jones et al (1999).10