and dysphoria/negative affect associated with ethanol withdrawal. Behavioral measures of anhedonia (e.g., brain stimulation reward model utilizing intracranial self-stimulation procedures) would be useful and also may provide opportunities to track the time course of such behavioral changes in relation to adaptations in DYN/KOR activity. Like ethanol exposure, stress is known to be a potent activator of the DYN/KOR system, yet relatively few studies have focused on how such changes may influence the motivational effects of ethanol. The complex reciprocal relationship between stress and ethanol is beginning to be more fully elucidated at the brain and behavior levels (Becker, 2012; Becker et al., 2011; Koob, 2013; Noori et al., 2014; Sinha, 2012; Spanagel et al., 2014; Uhart and Wand, 2009). Studies aimed at understanding the contribution of the DYN/KOR system to this dynamic ethanol-stress relationship are timely and needed in the field. This, in turn, will provide valuable insight about KOR pharmacological agents as potential therapeutics for comorbidity of alcohol use disorders and stress-related disorders (depression, PTSD) (Crowley and Kash, 2015; Lalanne et al., 2014).
