Behavioral Animal Models and Neural-Circuit Framework of Depressive Disorder

 Xiangyun Tian1,2 · Scott J. Russo3,4 · Long Li1,2
1 State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China 
2 University of the Chinese Academy of Sciences, Beijing 100049, China 
3 Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA 
4 Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA

Abstract
Depressive disorder is a chronic, recurring, and potentially life-endangering neuropsychiatric disease. According to a report by the World Health Organization, the global population suffering from depression is experiencing a significant annual increase. Despite its prevalence and considerable impact on people, little is known about its pathogenesis. One major reason is the scarcity of reliable animal models due to the absence of consensus on the pathology and etiology of depression. Furthermore, the neural circuit mechanism of depression induced by various factors is particularly complex. Considering the variability in depressive behavior patterns and neurobiological mechanisms among different animal models of depression, a comparison between the neural circuits of depression induced by various factors is essential for its treatment. In this review, we mainly summarize the most widely used behavioral animal models and neural circuits under different triggers of depression, aiming to provide a theoretical basis for depression prevention.

Keywords
Depression · Animal models · Stress · Neural circuits