Incubation of methamphetamine but not heroin craving after voluntary abstinence in male and female rats
We recently introduced an animal model of incubation of methamphetamine craving after choice-based voluntary abstinence in male rats. Here we studied the generality of this phenomenon to (1) female rats, and (2) male and female rats with a history of heroin self-administration. We first trained rats to self-administer palatable food pellets for 6 days (6?h per day) for either methamphetamine (0.1?mg/kg/infusion) or heroin (0.1?mg/kg/infusion) for 12 days (6?h/day). We then assessed relapse to drug seeking under extinction conditions after 1 and 21 abstinence days.