OPRK1 and Anxiety: These results are in line with literature showing KOR antagonists can block anxiety-like behaviors precipitated by acute withdrawal from alcohol vapor (Valdez and Harshberger, 2012; Rose et al., 2016) and suppress alcohol self-administration in post-dependent rats (Walker and Koob, 2008; Schank et al., 2012; Kissler et al., 2014).