Katie Robey ‘19, a biochemistry major and neuroscience minor, and biology major and neuroscience minor Brooke Steinhoff ’19 both received grants in support of their joint St. Mary’s Project in Psychology, “Antidepressant efficacy of L-655,708 following infusion into the medial prefrontal cortex,” which is being mentored by Dr. Aileen Bailey.
Project abstract: Major depressive disorder (MDD) is one of the most prevalent mental illnesses in the United States, as it affects around 1 in 5 Americans at some point in their lifetime (Hasin et al.,
2018) . Selective Serotonin Reuptake Inhibitors (SSRIs) are the most common therapeutic treatment employed, despite the fact that these prescriptions are only effective in half of patients
and take several weeks for symptomatic relief to be experienced (Fischell, Van Dyke, Kvarta, LeGates, & Thompson, 2015) . Previous studies have found evidence that links the etiology of
depression with decreases in glutamatergic transmission and expression in neuronal regions associated with reward processing (Thompson et al., 2015; Yuen et al., 2012). The present study
aims at investigating the fast-acting antidepressant value of the drug L-655,708, a negative allosteric modulator of GABA A receptors containing alpha-5 subunits, following direct infusions
into the medial prefrontal cortex (mPFC). Baseline depressive-like behaviors will be measured through the employment of the novelty-suppressed feeding (NSF) test, social interaction test
(SIT), sucrose preference test (SPT), and open field test (OFT) in an animal model of depression. Following 28 days of exposure to a chronic unpredictable stress paradigm, the rats will be
surgically implanted with guide cannulas and will receive direct infusions into the mPFC of either L-655,708 or a vehicle. We hypothesize that the rats that receive L-655,708 will show
significant decreases in the depressive-like behaviors measured by each of the tests as compared to the vehicle group. The outcome of this study may provide support for targeting the mPFC as
an option for the therapeutic treatment of depression.