Figure 8.

Synaptic inputs to OXT neurons in the PVN and possibly the SON. In this scheme, the CS + signal is carried by augmented incerto-hypothalamic DA transmission driven by sensitized mesolimbic DA. The US signal is carried by opioid transmission acting on μ opioid receptors. Although this signal inhibits OXT cell membranes, it leads to an augmentation of CD38 gene transcription, mobilization of Ca²⁺, and sensitization of OXT transmission when neurons are stimulated (in this case by DA, but potentially also by OXT and N-methyl D-aspartate [NMDA] glutamate [GLU] inputs).