A Methodology for Determining the Dendritic Complexity of Hippocampal Neurons in Chronically Stressed Rats

Chronic stress is a risk factor for many diseases that impact the brain, including Alzheimer’s Disease. Unlike acute stress, chronic stress reduces neuronal plasticity, which can lead to neuronal remodeling and suppression. This project investigates the effect of stress on the dendritic complexity of hippocampal neurons in rats, demonstrating a methodology for procuring and analyzing these neurons. The brains of the 160 rats from the Sustained Threat and Timing (STAT) experiment were frozen. The STAT experiment investigated the effect chronic variable stress had on prospective and retrospective timing in rodents. Using a cryostat, thin coronal slices of brain tissue were placed on microscopic slides. The tissue samples were then stained using the Golgi method of silver staining. Hippocampal neurons were assessed using Sholl Analysis; the dendritic complexity of these neurons was quantified. The method of using Sholl Analysis was found to be an effective process in measuring dendritic length of hippocampal neurons.