Apparatus, protocol, and paradigm that quantitatively measures mouse stress levels through pupil dilation.

Measurement of stress is imperative to psychological and mental disorder mouse model characterization, especially to determine the efficacy of drugs. Yet, conventional behavioral testing relies on indirect measures of stress that are difficult to interpret, time-intensive, and incompatible with concurrent electrophysiology, live imaging, or optogenetics.

University of Utah researchers have developed a protocol, paradigm, and apparatus to measure acute pupil dilation as a quantitative measure of mouse stress. The test is run in a sound and light isolated box, where tones are played to startle the mice. The apparatus is head-fixed, enabling concurrent high-resolution testing of brain activity.

• Measures stress quantitatively through adrenergic fight-or-flight response.
• Quantifies stress within seconds, enabling a full test in about 30 minutes.
• Offers capability to test anxiolytic or anti-depressant drugs and medication side effects.
• Enables concurrent brain testing.

Tränkner, Dimitri et al. “A Microglia Sublineage Protects from Sex-Linked Anxiety Symptoms and Obsessive Compulsion.” Cell reports vol. 29,4 (2019): 791-799.e3. doi:10.1016/j.celrep.2019.09.045

Lucia Irazabal
lu.irazabal@utah.edu