Preconception maternal cocaine self-administration increases the reinforcing efficacy of cocaine in male offspring.

RATIONALE: Although the influence of gestational cocaine exposure on offspring has been the focus of a sustained research effort, the effect of preconception cocaine self-administration by dams on progeny has received far less attention.
METHOD: In the current study, adult female rats were allowed to self-administer cocaine 2 h a day for 60 days and then after a 10-day wash out period, bred to naïve males. Maternal behavior was measured in dams until weaning. When male and female progeny reached adulthood, anxiety-like behavior, memory, and cocaine self-administration were assessed in separate cohorts of rats.
RESULTS: Despite a total of at least 30 days of cocaine abstinence, the quality of maternal behaviors was negatively affected by previous cocaine exposure as reflected by less time spent with pups as well as an excess of other maladaptive maternal behaviors. Measures of anxiety-like behavior and memory were not affected by maternal cocaine intake in either male or female offspring. In contrast, male, but not female, the progeny of dams exposed to cocaine showed increased reinforcing efficacy of cocaine as measured by cocaine self-administration under a progressive ratio schedule. The fact that cocaine self-administration was influenced only in the male offspring of cocaine-exposed dams argues against this phenotype being linked to altered maternal behavior, although this possibility cannot be ruled out completely.
CONCLUSIONS: Collectively, these results indicate that preconception cocaine self-administration by dams results in the relatively selective enhancement of cocaine addiction-like behavior in male offspring.