A modified tail suspension test for the assessment of behavioral despair in mice after stroke

Stroke survivors usually suffer from mood and emotional disturbances, especially depression. However, research on poststroke depression (PSD) is limited by the measurement of behavioral despair in animals. The tail suspension test (TST) is a classic method for assessing behavioral despair in mice based on an increased immobility time. Ischemic mice assessed using the classic TST instinctively struggled because of incoordination, which influenced the immobility time and caused misleading results. In this study, we modified the classic TST equipment by introducing a smooth and transparent plate inclined at 60^° to help the suspended mouse maintain its balance during testing, without an obvious reduction in the aversive stress occurring during suspension. Finally, we validated the modified TST using mouse models of chronic mild stress, middle cerebral artery occlusion and PSD. Thus, the modified TST is an efficient method for assessing behavioral despair in mice with impaired motor coordination, especially after stroke.