Tail Suspension Test
The tail suspension test (TST) has become one of the most widely used models for assessing antidepressant-like activity in mice. The test is based on the fact that animals subjected to the short-term, inescapable stress of being suspended by their tail, will develop an immobile posture. Immobility is defined as the absence of initiated movements and includes passive swaying.
Square Test Cubicle (Med Associates, St. Albans, VT) equipped with a strain gauge from which the mouse can be suspended.
Suspended mice by the tail with tape from the strain gauge (strain gauge is the hook connected to the vertical bar). Mice should be positioned such that the base of their tail is aligned with the bottom of the bar. Each mouse is given 1 trial that last 6 minutes. The total duration of immobility is calculated as the time the force of the mouse's movements is below a preset threshold.
- If a mouse climbs its tail gently pull it back down and continue trial
- Mice that climb their tails for more than 20% of the trial (i.e. 72 seconds) will eliminated from the final analysis
Duration of immobility. The duration of immobility is the main parameter measured. This is calculated from the cumulated time during which the animals movements do not exceed the threshold determined by the level-filtering device. This will need to be set by the experimenter.