Prenatal stress and pubertal anxiety are related with adult vulnerability to cocaine-induced conditioning place preference?.

PASTOR V; ANTONELLI , MC; PALLARES, ME.; OLSZEVICKI S

San Diego

Congreso; 46th Annual Meeting of the Society for Neuroscience; 2016

Society for Neuroscience

Increasing evidences point to the influence of early life adversity on the development of substance use disorders, suggesting that drug addiction could be considered a developmental disorder. Nonetheless, no studies today have focused on the relationship between pubertal behavioral traits and adult vulnerability to drug reward in prenatally stressed rats. We designed the present study to determine if anxiety or novelty-induced locomotor activity during puberty have any relationship with individual differences to cocaine-induced conditioned place preference (CPP) during adulthood and the influence of prenatal stress on CPP vulnerability. Pregnant dams were randomly assigned to either the non-prenatal stress (NPS) or the prenatal stress (PS) group. Male offspring were tested for anxiety and novelty response during puberty (P35) and left undisturbed until P90, when we trained them in a 4-trial CPP with cocaine (20 mg/kg). Cocaine-treated animals were classified based on their CPP score in LowCPP or HighCPP (i.e., a CPP score below or above the mean of the sample, respectively). Notably, HighCPP group was further represented by PS (71%) than NPS rats (29%) supporting the notion that prenatal stress is a risk factor for cocaine vulnerability. The analysis of behavioral traits during puberty showed that novelty response was the same in LowCPP and HighCPP and no differences were found between NPS and PS groups neither in novelty response nor in rearing or grooming behaviors. Interestingly, for NPS group, HighCPP animals were more anxious than LowCPP animals during puberty. In contrast, in PS group, HighCPP animals were less anxious than LowCPP animals, evidenced not only by the total time spend in open arms but also by the number of entries to open arms in the elevated plus maze. These results indicate, that adult Wistar rats differed in their CPP score, with some exhibiting a greater preference than others (HighCPP and LowCPP). Moreover, HighCPP and LowCPP differed in their anxiety traits during puberty in an opposite way in NPS vs. PS rats; suggesting that the relationship between adolescent anxiety and adult vulnerability to cocaine reward assessed by CPP depends on the exposure of the offspring to gestational stress. Our findings also emphasize the importance of using animal models based on differential individual behavioral profiles as an effective strategy for identifying genes and molecular mechanisms that can promote vulnerability to drug addiction.