Adaptations in the DYN/KOR system have been also observed during ethanol withdrawal. For example, increased DYN-A stimulated GTPγS coupling and immunoreactivity were reported in the amygdala during withdrawal from chronic ethanol vapor exposure, indicative of greater KOR signaling and dynorphin peptide expression (Kissler et al., 2014). The DYN/KOR system also has been implicated in ethanol withdrawal-related seizures. Using mice selectively bred for high and low seizure susceptibility during ethanol withdrawal, greater prodynorphin mRNA, greater KOR binding, and greater KOR density were observed in withdrawal seizure-prone (WSP) mice relative to withdrawal seizure-resistant (WSR) mice following withdrawal from chronic ethanol vapor exposure (Beadles-Bohling et al., 2000; Beadles-Bohling and Wiren, 2005).
