Enduring Anxiolytic Effect of Adolescent Ketamine Exposure in Female c57BL/6 Mice

RM 217

Major Depressive Disorder (MDD) is one of the most severe and potentially debilitating forms of mood disorder affecting people across the globe. Nevertheless, MDD has only recently been recognized to affect pediatric populations, so the long-term effects of pharmacological treatment approaches for managing this condition have garnered a great deal of attention. Today, fluoxetine, a selective serotonin reuptake inhibitor (SSRI), is the only pharmacological agent approved by the FDA for the treatment of children and adolescents, ages 7-18, who suffer from MDD. Even though fluoxetine has been shown to be somewhat effective in the treatment of adult MDD, there is a lack of evidence suggesting that it is a reliable treatment in pediatric populations. Ketamine, an N-methyl-D-Aspartate receptor antagonist, has recently been proposed as a possible antidepressant alternative at both the clinical and preclinical level, showing both rapid-acting and long-lasting effects, when compared to SSRI’s such as fluoxetine. The purpose of this experiment was to delineate the long-lasting neurobehavioral effects of chronic ketamine exposure, especially when administered at early stages of development, in female mice. Particularly, our goal was to understand the role ketamine plays on the mediation of potential anxiogenic (anxiety eliciting) responses in adulthood with the use of the Elevated Plus Maze (EPM). The results the animals who received the chronic regiment of ketamine during adolescence displayed significantly less sensitivity to anxiogenic stimuli in adulthood, as they spent more time in the open arms of the elevated plus maze than the animals pretreated with saline.