Induction and Evaluation of Depression in Mice Through Chronic Stress Exposure

Induce depression in a test mouse through exposure to chronic stress and compare it to a control mouse.

Apply daily stressors to the test mouse, including food and water deprivation, confinement in a restrainer, isolation in a cage without bedding, placement in a wet or crowded cage, and forced swimming in ice-cold water.

These stressors trigger the release of corticosterone, a stress hormone.

Corticosterone binds to its receptors on neurons, causing an excessive release of glutamate, an excitatory neurotransmitter.

Excessive glutamate over-activates calcium-permeable ionotropic receptors, inducing continuous calcium influx, which results in neuronal death, a process called excitotoxicity. 

The loss of neurons in the hippocampus and prefrontal cortex, regions essential for mood regulation, disrupts signal transmission and triggers symptoms of depression.

Compared to the control mouse, observe changes in coat condition due to stress-induced reductions in grooming behavior and weight loss due to reduced appetite in the test mouse, indicating depression.