Oxycodone Decreases Dendritic Complexity in Female but not Male Rat Striatal Neurons In Vitro

•Oxycodone decreases dendritic complexity in female striatal neurons.•Oxycodone decreases the number of non-primary dendrites in female striatal neurons.•Oxycodone does not alter dendritic complexity in male striatal neurons.•Findings indicate chromosomal differences contribute to sex-dependent effects of oxycodone on striatal dendritic complexity. The use of oxycodone in the past two decades has dramatically risen, yet the amount of research regarding how it impacts neuronal health is lacking. As prescription use and misuse in women of reproductive age increases there has been a corresponding increase in the number of infants who have been exposed to oxycodone in utero. Given the critical role of the striatum in motor control and reward regulation, the aim of the current study was to examine the effects of oxycodone on developing rat striatal neurons. Sex-specific effects of oxycodone on neuronal cytoarchitecture were examined in cultured rat striatal neurons with a primary focus on dendritic arborization. Neurons were extracted from either male or female embryonic day 18 rat striata and cultured and exposed to varying concentrations of oxycodone over a ten-day period. Dendritic complexity of the neurons was measured using Sholl analysis. Results indicate that oxycodone inhibits dendritic complexity in a dose-dependent manner in female but not male striatal neurons. Additional analysis indicated the number of non-primary dendrites in female striatal neurons significantly decreased with increasing concentrations of oxycodone, while the number of primary dendrites as well as the length of primary and non-primary dendrites was unaffected by oxycodone treatment in both sexes. These in vitro findings demonstrate sex-specific effects of oxycodone on the development of striatal dendritic architecture which may be important for understanding the effects of oxycodone exposure in utero.