Chunk #65 — 5. Procedures for evaluating pharmacological treatments targeting alcohol abuse and dependence — 5.7. Relapse of ethanol drinking in the operant chamber
The effect of forced deprivations on relapse drinking such as the ADE can also be measured using operant procedures. Once maintenance responding for ethanol has been established, a period of forced deprivation can be implemented by keeping the animals in their home cage for a period of weeks or days. Upon their return to the operant chamber, an increase in responding for ethanol above that which was seen prior to the forced deprivation is evidence of an ADE. The cycle of daily operant sessions with periods of forced deprivations can be repeated to examine if the deprivation effect increases in magnitude and/or duration after repeated deprivations. Animals can be pretreated with different pharmacotherapies prior to reintroduction to the operant chamber after forced deprivation in order to examine the ability of these compounds to curb relapse-like self-administration. For example, it has been shown that LY404039, an mGluR2/3 agonist (Rodd et al., 2006), and SB-334867, an orexin1 receptor antagonist (Dhaher et al., 2010), reduce ethanol-seeking and relapse-like (i.e., ADE) operant ethanol responding, respectively, by P rats. In another study with P rats,
