Author’s Note: This was a research study performed during my undergraduate studies in conjunction with a neuroscience supervisor and a graduate student. The findings from this study were showcased at several health science and neuroscience conferences.
Nicotine replacement therapy (NRT) is one of the most common comprehensive assistance provided to the general population to help in smoking cessation. Most importantly, several studies suggest that, in recent years, female smokers are opting for the NRT treatment mainly while they are pregnant or breastfeeding. However, the limited studies on the effects of this treatment on the offspring, specifically the long-term effects of these lower doses of nicotine exposure, are not yet well understood. Previous studies also suggest that nicotine exposure pre- or neo-natally may be associated with neurobehavioral consequences later in life. Therefore, the objective of this research study was to evaluate the neurobehavioral changes, primarily risk-taking behaviours, in adolescent rats exposed to nicotine in early life.
During the first two postnatal days (PND1 & 2), rat pups from multiple litters received subcutaneous nicotine injections. At the time of weaning on PND21, same-sex pups were housed two per cage. During peri-adolescence, on PND 35-41, the animals were first habituated to the testing apparatus and then their behaviour was assessed in the predator odour paradigm. This paradigm serves to evaluate risk behaviour when faced with a fear and stress-inducing predator odour. This paradigm is typically used in adults but our interest lies in the peri-adolescent period – a time period when the frontal cortex is still not fully developed and reasoning and impulsivity are often problematic. Findings from this research will help contribute further information on the effects of early life nicotine exposure, particularly in an understudied population – peri-adolescents – specifically as it pertains to risk taking behaviours.
Attached below is a poster presentation of findings from this research study.
Upon completion of the experiment and research observations, our findings suggest that nicotine exposure had no effect on risk taking behaviours during peri-adolescence. However, this is also considering the limitations from our findings, that may/may not have altered our results. For future directions, I employ that every (or most) external variable that may skew findings’ results be eliminated or controlled and a larger sample of rats be implemented.
For more studies like this, check out “Adolescent Brain Development and the Risk for Alcohol and Other Drug Problems” by Sunita Bava & Susan F. Tapert, “Nicotine Exposure in Breastfed Infant” by Dahlstrom et al., “Prenatal nicotine exposure and child behavioural problems” by Carla Tiesler & Joachim Heinrich, “The Long-Term Effects of Perinatal Nicotine Exposure on Neurologic Development” by Jane Blood-Siegfried & Elizabeth Rende, and so many more.