Previous research suggests that developmental nicotine exposure (DNE) can cause negative impacts on the hippocampus, and inhibit function of the CA3/CA1 region (Bruin et al. 2010). The CA3/CA1 region in the hippocampus are primarily responsible for completing the underlying process of memory formation (Cherubini et al. 2015). The memory impairments caused by DNE have no known cure, but experimental research suggests that administration of the ADHD medication Methylphenidate may improve spatial and working memory in mammals (Contreras et al., 2022). Because of this, I propose that studying synaptic transmission from an electrophysiological lens may provide insight to the mechanism that produces memory loss in mammals caused by DNE. With this insight, it may be possible to design a treatment plan to improve this defect.

 I will use an electrophysiological rig that will report extracellular membrane readings (field excitatory postsynaptic potential or fESP) of synapses in the CA3/CA1 region of the hippocampus from healthy animals compared to animals exposed to nicotine. To obtain the mice for the electrophysiology experiments, there will be 2 cages, each containing 4 female mice. One group will receive a nicotine and saccharine solution to consume, while the other will receive a water and saccharine solution. After 4 weeks of consumption, 1 male mouse will be placed in each of the cages. The mice will breed, and the offspring will mature to 4 weeks old before they are euthanized and used for the electrophysiology experiments. The extracellular readings (fESPs) from the CA3/CA1 region will be recorded, and the slopes and amplitudes of the fESPs will be analyzed. Weaker slopes and amplitudes indicate a weakened synaptic transmission. 

In addition to the electrophysiology experiments, neurotransmitter release from DNE hippocampal slices and healthy hippocampal slices will be quantified and compared. Hippocampal slices will be placed in the wells of a 6 well plate that already contain pseudo cerebral spinal fluid. There is a small hole punctured over each well, so that a needle may fit through the opening and collect a sample of the pseudo-cerebral spinal fluid at several predetermined time intervals. A glutamate activity assay kit will be used to determine the concentration of glutamate in DNE slices compared to healthy slices.