Chunk #20 — Effects of DYN/KOR Activity on Ethanol-Conditioned Behavior and Consumption — Operant Ethanol Self-Administration and Relapse-Like Behavior
A greater number of studies have assessed consequences of KOR blockade on operant ethanol self-administration. As in home-cage drinking studies, KOR antagonists typically reduced self-administration (e.g., Schank et al., 2012a; Cashman and Azar, 2014; Rorick-Kehn et al., 2014). Further, the ability of KOR blockade to reduce ethanol self-administration was consistently shown to be selective for subjects demonstrating elevated consumption associated with ethanol dependence (e.g., Kissler et al., 2014; Walker et al., 2011; Walker et al., 2008). In a study that observed reduced ethanol self-administration among non-dependent subjects following KOR antagonist administration (Schank et al., 2012a), twice the dose of nor-BNI (30 mg/kg) was required to produce an effect similar to that observed at a lower dose (15 mg/kg) in ethanol-dependent rats (Walker et al., 2011). This provides additional evidence that ethanol-dependent subjects are more sensitive to effects of KOR antagonists on drinking compared to non-dependent subjects. Non-dependent P-rats were also shown to be sensitive to the effects of nor-BNI on ethanol self-administration responding under fixed and progressive ratio schedules, spontaneous recovery, and relapse (Cashman and Azar, 2014; Rorick-Kehn et al.,
