Below you will find the first draft of the abstract that summarizes my summer research project in the Kuhn lab. Please keep in mind that this abstract is very preliminary especially regarding result interpretation and conclusions. Enjoy with a grain of salt.
The neurobiology of depression remains largely unknown and has not been studied in respect to sex-differences. Rapid tryptophan depletion (RTD) is a method used to lower levels of endogenous tryptophan (TRP) and serotonin (5-HT) and was used in this study to explore possible sex differences in the way rats react to tryptophan depletion. This study administered one of three treatments to 36 rats: 1) RTD, 2) a balanced amino acid treatment (BAL), or 3) None. Plasma and brain samples were collected and later analyzed using high performance liquid chromatography (HPLC) to determine concentrations of TRP and 5-HT. While RTD had similar depletion effects in the plasma of both females and males, there were significant differences in how TRP and 5-HT levels shifted in the hippocampal brain region of males and females. Compared to female controls, RTD females experienced significantly lowered levels of 5-HT and TRP, more so than RTD males compared to male controls. This suggest that sex-mediated differences in the serotonergic systems of rats is responsible for the different responses to tryptophan depletion. Further work must explore this neurobiological distinction between male and female rats and clinical research should focus on determining whether a similar difference exists in humans.