Paternal morphine exposure enhances morphine self-administration and induces region-specific neural adaptations in reward-related brain regions of male offspring

Despite the prevalence of opioid exposure throughout human populations, little is known about the impact of paternal (male-line) opioid use on progeny; METHODS: Adult male rats self-administered morphine or saline for 60 days. These sires were then bred to drug-naïve dams to produce first-generation (F1) offspring.

Morphine, cocaine, and nicotine self-administration were evaluated in adult F1 progeny. Molecular correlates of addiction-like behaviors in reward-related brain regions were also measured in a cohort of drug-naïve F1 offspring; RESULTS: Male offspring bred from morphine-exposed sires exhibited a dose-dependent increase in morphine self-administration and increased motivation to earn morphine infusions under a progressive ratio schedule of reinforcement.