• KSBNS 2024


Original Article

Exp Neurobiol 2014; 23(3): 215-223

Published online September 30, 2014

© The Korean Society for Brain and Neural Sciences

Implementation of a Two-dimensional Behavior Matrix to Distinguish Individuals with Differential Depression States in a Rodent Model of Depression

Jin-Young Park1#, Tae-Kyung Kim1#, Juli Choi1, Jung-Eun Lee1, Hannah Kim1, Eun-Hwa Lee1 and Pyung-Lim Han1,2,3*

Departments of 1Brain and Cognitive Sciences, 2Chemistry and Nano Science, and 3Brain Disease Research Institute, Ewha Womans University, Seoul 120-750, Korea

Correspondence to: *To whom correspondence should be addressed.
TEL: 82-2-3277-4130, FAX: 82-2-3277-3419
#These authors contributed equally to this work.

Received: July 1, 2014; Revised: August 6, 2014; Accepted: August 7, 2014


Animal models of depression are used to study pathophysiology of depression and to advance therapeutic strategies. Stress-induced depression models in rodents are widely used. However, amenable behavioral criteria and experimental procedures that are suitable for animal models have not been established. Given that depression is clinically diagnosed by multiple symptomatic criteria and stress effects are imposed to the brain non-specifically in stress-induced depression models, analyses of depression states in rodents using multiple symptomatic criteria may provide more power than any methods relying on a single symptomatic criterion. To address this, C57BL/6 inbred mice were restrained for 2 h daily for 14 d, and depression states of individual mice were assessed using the U-field test, behavioral assessment developed to measure animal's sociability, and the tail suspension test and/or forced swim test, which are the typical methods that measure psychomotor withdrawal states. Although the majority of these mice showed severe depressive behaviors in both tests, a significant proportion of them, which were all inbred mice and received the same amount of restraints, expressed differential depression states in the sociability test and psychomotor withdrawal tests. To easily read-out differential depression states of individuals in two different tests, a standard method and basic parameters required to construct two-way behavior matrix were introduced. The utility and features of this two-way behavior analysis method for studies of different depressive states of individuals were discussed.

Keywords: depression, sociability, psychomotor retardation, U-field test